rust/src/libsyntax/print/pprust.rs

3085 lines
112 KiB
Rust

// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
pub use self::AnnNode::*;
use abi;
use ast;
use ast::{RegionTyParamBound, TraitTyParamBound, TraitBoundModifier};
use ast_util;
use attr;
use owned_slice::OwnedSlice;
use attr::{AttrMetaMethods, AttributeMethods};
use codemap::{self, CodeMap, BytePos};
use diagnostic;
use parse::token::{self, BinOpToken, Token, InternedString};
use parse::lexer::comments;
use parse;
use print::pp::{self, break_offset, word, space, zerobreak, hardbreak};
use print::pp::{Breaks, eof};
use print::pp::Breaks::{Consistent, Inconsistent};
use ptr::P;
use std_inject;
use std::ascii;
use std::io::{self, Write, Read};
use std::iter;
pub enum AnnNode<'a> {
NodeIdent(&'a ast::Ident),
NodeName(&'a ast::Name),
NodeBlock(&'a ast::Block),
NodeItem(&'a ast::Item),
NodeSubItem(ast::NodeId),
NodeExpr(&'a ast::Expr),
NodePat(&'a ast::Pat),
}
pub trait PpAnn {
fn pre(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) }
fn post(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) }
}
#[derive(Copy, Clone)]
pub struct NoAnn;
impl PpAnn for NoAnn {}
#[derive(Copy, Clone)]
pub struct CurrentCommentAndLiteral {
cur_cmnt: usize,
cur_lit: usize,
}
pub struct State<'a> {
pub s: pp::Printer<'a>,
cm: Option<&'a CodeMap>,
comments: Option<Vec<comments::Comment> >,
literals: Option<Vec<comments::Literal> >,
cur_cmnt_and_lit: CurrentCommentAndLiteral,
boxes: Vec<pp::Breaks>,
ann: &'a (PpAnn+'a),
}
pub fn rust_printer<'a>(writer: Box<Write+'a>) -> State<'a> {
static NO_ANN: NoAnn = NoAnn;
rust_printer_annotated(writer, &NO_ANN)
}
pub fn rust_printer_annotated<'a>(writer: Box<Write+'a>,
ann: &'a PpAnn) -> State<'a> {
State {
s: pp::mk_printer(writer, default_columns),
cm: None,
comments: None,
literals: None,
cur_cmnt_and_lit: CurrentCommentAndLiteral {
cur_cmnt: 0,
cur_lit: 0
},
boxes: Vec::new(),
ann: ann,
}
}
#[allow(non_upper_case_globals)]
pub const indent_unit: usize = 4;
#[allow(non_upper_case_globals)]
pub const default_columns: usize = 78;
/// Requires you to pass an input filename and reader so that
/// it can scan the input text for comments and literals to
/// copy forward.
pub fn print_crate<'a>(cm: &'a CodeMap,
span_diagnostic: &diagnostic::SpanHandler,
krate: &ast::Crate,
filename: String,
input: &mut Read,
out: Box<Write+'a>,
ann: &'a PpAnn,
is_expanded: bool) -> io::Result<()> {
let mut s = State::new_from_input(cm,
span_diagnostic,
filename,
input,
out,
ann,
is_expanded);
if is_expanded && std_inject::use_std(krate) {
// We need to print `#![no_std]` (and its feature gate) so that
// compiling pretty-printed source won't inject libstd again.
// However we don't want these attributes in the AST because
// of the feature gate, so we fake them up here.
let no_std_meta = attr::mk_word_item(InternedString::new("no_std"));
// #![feature(no_std)]
let fake_attr = attr::mk_attr_inner(attr::mk_attr_id(),
attr::mk_list_item(InternedString::new("feature"),
vec![no_std_meta.clone()]));
try!(s.print_attribute(&fake_attr));
// #![no_std]
let fake_attr = attr::mk_attr_inner(attr::mk_attr_id(), no_std_meta);
try!(s.print_attribute(&fake_attr));
}
try!(s.print_mod(&krate.module, &krate.attrs));
try!(s.print_remaining_comments());
eof(&mut s.s)
}
impl<'a> State<'a> {
pub fn new_from_input(cm: &'a CodeMap,
span_diagnostic: &diagnostic::SpanHandler,
filename: String,
input: &mut Read,
out: Box<Write+'a>,
ann: &'a PpAnn,
is_expanded: bool) -> State<'a> {
let (cmnts, lits) = comments::gather_comments_and_literals(
span_diagnostic,
filename,
input);
State::new(
cm,
out,
ann,
Some(cmnts),
// If the code is post expansion, don't use the table of
// literals, since it doesn't correspond with the literals
// in the AST anymore.
if is_expanded { None } else { Some(lits) })
}
pub fn new(cm: &'a CodeMap,
out: Box<Write+'a>,
ann: &'a PpAnn,
comments: Option<Vec<comments::Comment>>,
literals: Option<Vec<comments::Literal>>) -> State<'a> {
State {
s: pp::mk_printer(out, default_columns),
cm: Some(cm),
comments: comments,
literals: literals,
cur_cmnt_and_lit: CurrentCommentAndLiteral {
cur_cmnt: 0,
cur_lit: 0
},
boxes: Vec::new(),
ann: ann,
}
}
}
pub fn to_string<F>(f: F) -> String where
F: FnOnce(&mut State) -> io::Result<()>,
{
let mut wr = Vec::new();
{
let mut printer = rust_printer(Box::new(&mut wr));
f(&mut printer).unwrap();
eof(&mut printer.s).unwrap();
}
String::from_utf8(wr).unwrap()
}
pub fn binop_to_string(op: BinOpToken) -> &'static str {
match op {
token::Plus => "+",
token::Minus => "-",
token::Star => "*",
token::Slash => "/",
token::Percent => "%",
token::Caret => "^",
token::And => "&",
token::Or => "|",
token::Shl => "<<",
token::Shr => ">>",
}
}
pub fn token_to_string(tok: &Token) -> String {
match *tok {
token::Eq => "=".to_string(),
token::Lt => "<".to_string(),
token::Le => "<=".to_string(),
token::EqEq => "==".to_string(),
token::Ne => "!=".to_string(),
token::Ge => ">=".to_string(),
token::Gt => ">".to_string(),
token::Not => "!".to_string(),
token::Tilde => "~".to_string(),
token::OrOr => "||".to_string(),
token::AndAnd => "&&".to_string(),
token::BinOp(op) => binop_to_string(op).to_string(),
token::BinOpEq(op) => format!("{}=", binop_to_string(op)),
/* Structural symbols */
token::At => "@".to_string(),
token::Dot => ".".to_string(),
token::DotDot => "..".to_string(),
token::DotDotDot => "...".to_string(),
token::Comma => ",".to_string(),
token::Semi => ";".to_string(),
token::Colon => ":".to_string(),
token::ModSep => "::".to_string(),
token::RArrow => "->".to_string(),
token::LArrow => "<-".to_string(),
token::FatArrow => "=>".to_string(),
token::OpenDelim(token::Paren) => "(".to_string(),
token::CloseDelim(token::Paren) => ")".to_string(),
token::OpenDelim(token::Bracket) => "[".to_string(),
token::CloseDelim(token::Bracket) => "]".to_string(),
token::OpenDelim(token::Brace) => "{".to_string(),
token::CloseDelim(token::Brace) => "}".to_string(),
token::Pound => "#".to_string(),
token::Dollar => "$".to_string(),
token::Question => "?".to_string(),
/* Literals */
token::Literal(lit, suf) => {
let mut out = match lit {
token::Byte(b) => format!("b'{}'", b.as_str()),
token::Char(c) => format!("'{}'", c.as_str()),
token::Float(c) => c.as_str().to_string(),
token::Integer(c) => c.as_str().to_string(),
token::Str_(s) => format!("\"{}\"", s.as_str()),
token::StrRaw(s, n) => format!("r{delim}\"{string}\"{delim}",
delim=repeat("#", n),
string=s.as_str()),
token::Binary(v) => format!("b\"{}\"", v.as_str()),
token::BinaryRaw(s, n) => format!("br{delim}\"{string}\"{delim}",
delim=repeat("#", n),
string=s.as_str()),
};
if let Some(s) = suf {
out.push_str(s.as_str())
}
out
}
/* Name components */
token::Ident(s, _) => token::get_ident(s).to_string(),
token::Lifetime(s) => format!("{}", token::get_ident(s)),
token::Underscore => "_".to_string(),
/* Other */
token::DocComment(s) => s.as_str().to_string(),
token::SubstNt(s, _) => format!("${}", s),
token::MatchNt(s, t, _, _) => format!("${}:{}", s, t),
token::Eof => "<eof>".to_string(),
token::Whitespace => " ".to_string(),
token::Comment => "/* */".to_string(),
token::Shebang(s) => format!("/* shebang: {}*/", s.as_str()),
token::SpecialVarNt(var) => format!("${}", var.as_str()),
token::Interpolated(ref nt) => match *nt {
token::NtExpr(ref e) => expr_to_string(&**e),
token::NtMeta(ref e) => meta_item_to_string(&**e),
token::NtTy(ref e) => ty_to_string(&**e),
token::NtPath(ref e) => path_to_string(&**e),
token::NtItem(ref e) => item_to_string(&**e),
token::NtBlock(ref e) => block_to_string(&**e),
token::NtStmt(ref e) => stmt_to_string(&**e),
token::NtPat(ref e) => pat_to_string(&**e),
token::NtIdent(ref e, _) => ident_to_string(&**e),
token::NtTT(ref e) => tt_to_string(&**e),
token::NtArm(ref e) => arm_to_string(&*e),
token::NtImplItem(ref e) => impl_item_to_string(&**e),
token::NtTraitItem(ref e) => trait_item_to_string(&**e),
token::NtGenerics(ref e) => generics_to_string(&*e),
token::NtWhereClause(ref e) => where_clause_to_string(&*e),
}
}
}
pub fn ty_to_string(ty: &ast::Ty) -> String {
to_string(|s| s.print_type(ty))
}
pub fn bounds_to_string(bounds: &[ast::TyParamBound]) -> String {
to_string(|s| s.print_bounds("", bounds))
}
pub fn pat_to_string(pat: &ast::Pat) -> String {
to_string(|s| s.print_pat(pat))
}
pub fn arm_to_string(arm: &ast::Arm) -> String {
to_string(|s| s.print_arm(arm))
}
pub fn expr_to_string(e: &ast::Expr) -> String {
to_string(|s| s.print_expr(e))
}
pub fn lifetime_to_string(e: &ast::Lifetime) -> String {
to_string(|s| s.print_lifetime(e))
}
pub fn tt_to_string(tt: &ast::TokenTree) -> String {
to_string(|s| s.print_tt(tt))
}
pub fn tts_to_string(tts: &[ast::TokenTree]) -> String {
to_string(|s| s.print_tts(tts))
}
pub fn stmt_to_string(stmt: &ast::Stmt) -> String {
to_string(|s| s.print_stmt(stmt))
}
pub fn attr_to_string(attr: &ast::Attribute) -> String {
to_string(|s| s.print_attribute(attr))
}
pub fn item_to_string(i: &ast::Item) -> String {
to_string(|s| s.print_item(i))
}
pub fn impl_item_to_string(i: &ast::ImplItem) -> String {
to_string(|s| s.print_impl_item(i))
}
pub fn trait_item_to_string(i: &ast::TraitItem) -> String {
to_string(|s| s.print_trait_item(i))
}
pub fn generics_to_string(generics: &ast::Generics) -> String {
to_string(|s| s.print_generics(generics))
}
pub fn where_clause_to_string(i: &ast::WhereClause) -> String {
to_string(|s| s.print_where_clause(i))
}
pub fn fn_block_to_string(p: &ast::FnDecl) -> String {
to_string(|s| s.print_fn_block_args(p))
}
pub fn path_to_string(p: &ast::Path) -> String {
to_string(|s| s.print_path(p, false, 0))
}
pub fn ident_to_string(id: &ast::Ident) -> String {
to_string(|s| s.print_ident(*id))
}
<<<<<<< HEAD
pub fn fun_to_string(decl: &ast::FnDecl, unsafety: ast::Unsafety, name: ast::Ident,
opt_explicit_self: Option<&ast::ExplicitSelf_>,
generics: &ast::Generics) -> String {
to_string(|s| {
||||||| parent of 61a958e... syntax: parse `const fn` for free functions and inherent methods.
pub fn fun_to_string(decl: &ast::FnDecl, unsafety: ast::Unsafety, name: ast::Ident,
opt_explicit_self: Option<&ast::ExplicitSelf_>,
generics: &ast::Generics) -> String {
$to_string(|s| {
=======
pub fn fun_to_string(decl: &ast::FnDecl,
unsafety: ast::Unsafety,
constness: ast::Constness,
name: ast::Ident,
opt_explicit_self: Option<&ast::ExplicitSelf_>,
generics: &ast::Generics)
-> String {
$to_string(|s| {
>>>>>>> 61a958e... syntax: parse `const fn` for free functions and inherent methods.
try!(s.head(""));
try!(s.print_fn(decl, unsafety, constness, abi::Rust, Some(name),
generics, opt_explicit_self, ast::Inherited));
try!(s.end()); // Close the head box
s.end() // Close the outer box
})
}
pub fn block_to_string(blk: &ast::Block) -> String {
to_string(|s| {
// containing cbox, will be closed by print-block at }
try!(s.cbox(indent_unit));
// head-ibox, will be closed by print-block after {
try!(s.ibox(0));
s.print_block(blk)
})
}
pub fn meta_item_to_string(mi: &ast::MetaItem) -> String {
to_string(|s| s.print_meta_item(mi))
}
pub fn attribute_to_string(attr: &ast::Attribute) -> String {
to_string(|s| s.print_attribute(attr))
}
pub fn lit_to_string(l: &ast::Lit) -> String {
to_string(|s| s.print_literal(l))
}
pub fn explicit_self_to_string(explicit_self: &ast::ExplicitSelf_) -> String {
to_string(|s| s.print_explicit_self(explicit_self, ast::MutImmutable).map(|_| {}))
}
pub fn variant_to_string(var: &ast::Variant) -> String {
to_string(|s| s.print_variant(var))
}
pub fn arg_to_string(arg: &ast::Arg) -> String {
to_string(|s| s.print_arg(arg))
}
pub fn mac_to_string(arg: &ast::Mac) -> String {
to_string(|s| s.print_mac(arg, ::parse::token::Paren))
}
pub fn visibility_qualified(vis: ast::Visibility, s: &str) -> String {
match vis {
ast::Public => format!("pub {}", s),
ast::Inherited => s.to_string()
}
}
fn needs_parentheses(expr: &ast::Expr) -> bool {
match expr.node {
ast::ExprAssign(..) | ast::ExprBinary(..) |
ast::ExprClosure(..) |
ast::ExprAssignOp(..) | ast::ExprCast(..) => true,
_ => false,
}
}
impl<'a> State<'a> {
pub fn ibox(&mut self, u: usize) -> io::Result<()> {
self.boxes.push(pp::Breaks::Inconsistent);
pp::ibox(&mut self.s, u)
}
pub fn end(&mut self) -> io::Result<()> {
self.boxes.pop().unwrap();
pp::end(&mut self.s)
}
pub fn cbox(&mut self, u: usize) -> io::Result<()> {
self.boxes.push(pp::Breaks::Consistent);
pp::cbox(&mut self.s, u)
}
// "raw box"
pub fn rbox(&mut self, u: usize, b: pp::Breaks) -> io::Result<()> {
self.boxes.push(b);
pp::rbox(&mut self.s, u, b)
}
pub fn nbsp(&mut self) -> io::Result<()> { word(&mut self.s, " ") }
pub fn word_nbsp(&mut self, w: &str) -> io::Result<()> {
try!(word(&mut self.s, w));
self.nbsp()
}
pub fn word_space(&mut self, w: &str) -> io::Result<()> {
try!(word(&mut self.s, w));
space(&mut self.s)
}
pub fn popen(&mut self) -> io::Result<()> { word(&mut self.s, "(") }
pub fn pclose(&mut self) -> io::Result<()> { word(&mut self.s, ")") }
pub fn head(&mut self, w: &str) -> io::Result<()> {
// outer-box is consistent
try!(self.cbox(indent_unit));
// head-box is inconsistent
try!(self.ibox(w.len() + 1));
// keyword that starts the head
if !w.is_empty() {
try!(self.word_nbsp(w));
}
Ok(())
}
pub fn bopen(&mut self) -> io::Result<()> {
try!(word(&mut self.s, "{"));
self.end() // close the head-box
}
pub fn bclose_(&mut self, span: codemap::Span,
indented: usize) -> io::Result<()> {
self.bclose_maybe_open(span, indented, true)
}
pub fn bclose_maybe_open (&mut self, span: codemap::Span,
indented: usize, close_box: bool) -> io::Result<()> {
try!(self.maybe_print_comment(span.hi));
try!(self.break_offset_if_not_bol(1, -(indented as isize)));
try!(word(&mut self.s, "}"));
if close_box {
try!(self.end()); // close the outer-box
}
Ok(())
}
pub fn bclose(&mut self, span: codemap::Span) -> io::Result<()> {
self.bclose_(span, indent_unit)
}
pub fn is_begin(&mut self) -> bool {
match self.s.last_token() {
pp::Token::Begin(_) => true,
_ => false,
}
}
pub fn is_end(&mut self) -> bool {
match self.s.last_token() {
pp::Token::End => true,
_ => false,
}
}
// is this the beginning of a line?
pub fn is_bol(&mut self) -> bool {
self.s.last_token().is_eof() || self.s.last_token().is_hardbreak_tok()
}
pub fn in_cbox(&self) -> bool {
match self.boxes.last() {
Some(&last_box) => last_box == pp::Breaks::Consistent,
None => false
}
}
pub fn hardbreak_if_not_bol(&mut self) -> io::Result<()> {
if !self.is_bol() {
try!(hardbreak(&mut self.s))
}
Ok(())
}
pub fn space_if_not_bol(&mut self) -> io::Result<()> {
if !self.is_bol() { try!(space(&mut self.s)); }
Ok(())
}
pub fn break_offset_if_not_bol(&mut self, n: usize,
off: isize) -> io::Result<()> {
if !self.is_bol() {
break_offset(&mut self.s, n, off)
} else {
if off != 0 && self.s.last_token().is_hardbreak_tok() {
// We do something pretty sketchy here: tuck the nonzero
// offset-adjustment we were going to deposit along with the
// break into the previous hardbreak.
self.s.replace_last_token(pp::hardbreak_tok_offset(off));
}
Ok(())
}
}
// Synthesizes a comment that was not textually present in the original source
// file.
pub fn synth_comment(&mut self, text: String) -> io::Result<()> {
try!(word(&mut self.s, "/*"));
try!(space(&mut self.s));
try!(word(&mut self.s, &text[..]));
try!(space(&mut self.s));
word(&mut self.s, "*/")
}
pub fn commasep<T, F>(&mut self, b: Breaks, elts: &[T], mut op: F) -> io::Result<()> where
F: FnMut(&mut State, &T) -> io::Result<()>,
{
try!(self.rbox(0, b));
let mut first = true;
for elt in elts {
if first { first = false; } else { try!(self.word_space(",")); }
try!(op(self, elt));
}
self.end()
}
pub fn commasep_cmnt<T, F, G>(&mut self,
b: Breaks,
elts: &[T],
mut op: F,
mut get_span: G) -> io::Result<()> where
F: FnMut(&mut State, &T) -> io::Result<()>,
G: FnMut(&T) -> codemap::Span,
{
try!(self.rbox(0, b));
let len = elts.len();
let mut i = 0;
for elt in elts {
try!(self.maybe_print_comment(get_span(elt).hi));
try!(op(self, elt));
i += 1;
if i < len {
try!(word(&mut self.s, ","));
try!(self.maybe_print_trailing_comment(get_span(elt),
Some(get_span(&elts[i]).hi)));
try!(self.space_if_not_bol());
}
}
self.end()
}
pub fn commasep_exprs(&mut self, b: Breaks,
exprs: &[P<ast::Expr>]) -> io::Result<()> {
self.commasep_cmnt(b, exprs, |s, e| s.print_expr(&**e), |e| e.span)
}
pub fn print_mod(&mut self, _mod: &ast::Mod,
attrs: &[ast::Attribute]) -> io::Result<()> {
try!(self.print_inner_attributes(attrs));
for item in &_mod.items {
try!(self.print_item(&**item));
}
Ok(())
}
pub fn print_foreign_mod(&mut self, nmod: &ast::ForeignMod,
attrs: &[ast::Attribute]) -> io::Result<()> {
try!(self.print_inner_attributes(attrs));
for item in &nmod.items {
try!(self.print_foreign_item(&**item));
}
Ok(())
}
pub fn print_opt_lifetime(&mut self,
lifetime: &Option<ast::Lifetime>) -> io::Result<()> {
if let Some(l) = *lifetime {
try!(self.print_lifetime(&l));
try!(self.nbsp());
}
Ok(())
}
pub fn print_type(&mut self, ty: &ast::Ty) -> io::Result<()> {
try!(self.maybe_print_comment(ty.span.lo));
try!(self.ibox(0));
match ty.node {
ast::TyVec(ref ty) => {
try!(word(&mut self.s, "["));
try!(self.print_type(&**ty));
try!(word(&mut self.s, "]"));
}
ast::TyPtr(ref mt) => {
try!(word(&mut self.s, "*"));
match mt.mutbl {
ast::MutMutable => try!(self.word_nbsp("mut")),
ast::MutImmutable => try!(self.word_nbsp("const")),
}
try!(self.print_type(&*mt.ty));
}
ast::TyRptr(ref lifetime, ref mt) => {
try!(word(&mut self.s, "&"));
try!(self.print_opt_lifetime(lifetime));
try!(self.print_mt(mt));
}
ast::TyTup(ref elts) => {
try!(self.popen());
try!(self.commasep(Inconsistent, &elts[..],
|s, ty| s.print_type(&**ty)));
if elts.len() == 1 {
try!(word(&mut self.s, ","));
}
try!(self.pclose());
}
ast::TyParen(ref typ) => {
try!(self.popen());
try!(self.print_type(&**typ));
try!(self.pclose());
}
ast::TyBareFn(ref f) => {
let generics = ast::Generics {
lifetimes: f.lifetimes.clone(),
ty_params: OwnedSlice::empty(),
where_clause: ast::WhereClause {
id: ast::DUMMY_NODE_ID,
predicates: Vec::new(),
},
};
try!(self.print_ty_fn(f.abi,
f.unsafety,
&*f.decl,
None,
&generics,
None));
}
ast::TyPath(None, ref path) => {
try!(self.print_path(path, false, 0));
}
ast::TyPath(Some(ref qself), ref path) => {
try!(self.print_qpath(path, qself, false))
}
ast::TyObjectSum(ref ty, ref bounds) => {
try!(self.print_type(&**ty));
try!(self.print_bounds("+", &bounds[..]));
}
ast::TyPolyTraitRef(ref bounds) => {
try!(self.print_bounds("", &bounds[..]));
}
ast::TyFixedLengthVec(ref ty, ref v) => {
try!(word(&mut self.s, "["));
try!(self.print_type(&**ty));
try!(word(&mut self.s, "; "));
try!(self.print_expr(&**v));
try!(word(&mut self.s, "]"));
}
ast::TyTypeof(ref e) => {
try!(word(&mut self.s, "typeof("));
try!(self.print_expr(&**e));
try!(word(&mut self.s, ")"));
}
ast::TyInfer => {
try!(word(&mut self.s, "_"));
}
}
self.end()
}
pub fn print_foreign_item(&mut self,
item: &ast::ForeignItem) -> io::Result<()> {
try!(self.hardbreak_if_not_bol());
try!(self.maybe_print_comment(item.span.lo));
try!(self.print_outer_attributes(&item.attrs));
match item.node {
ast::ForeignItemFn(ref decl, ref generics) => {
try!(self.head(""));
try!(self.print_fn(decl, ast::Unsafety::Normal,
ast::Constness::NotConst,
abi::Rust, Some(item.ident),
generics, None, item.vis));
try!(self.end()); // end head-ibox
try!(word(&mut self.s, ";"));
self.end() // end the outer fn box
}
ast::ForeignItemStatic(ref t, m) => {
try!(self.head(&visibility_qualified(item.vis,
"static")));
if m {
try!(self.word_space("mut"));
}
try!(self.print_ident(item.ident));
try!(self.word_space(":"));
try!(self.print_type(&**t));
try!(word(&mut self.s, ";"));
try!(self.end()); // end the head-ibox
self.end() // end the outer cbox
}
}
}
fn print_associated_const(&mut self,
ident: ast::Ident,
ty: &ast::Ty,
default: Option<&ast::Expr>,
vis: ast::Visibility)
-> io::Result<()>
{
try!(word(&mut self.s, &visibility_qualified(vis, "")));
try!(self.word_space("const"));
try!(self.print_ident(ident));
try!(self.word_space(":"));
try!(self.print_type(ty));
if let Some(expr) = default {
try!(space(&mut self.s));
try!(self.word_space("="));
try!(self.print_expr(expr));
}
word(&mut self.s, ";")
}
fn print_associated_type(&mut self,
ident: ast::Ident,
bounds: Option<&ast::TyParamBounds>,
ty: Option<&ast::Ty>)
-> io::Result<()> {
try!(self.word_space("type"));
try!(self.print_ident(ident));
if let Some(bounds) = bounds {
try!(self.print_bounds(":", bounds));
}
if let Some(ty) = ty {
try!(space(&mut self.s));
try!(self.word_space("="));
try!(self.print_type(ty));
}
word(&mut self.s, ";")
}
/// Pretty-print an item
pub fn print_item(&mut self, item: &ast::Item) -> io::Result<()> {
try!(self.hardbreak_if_not_bol());
try!(self.maybe_print_comment(item.span.lo));
try!(self.print_outer_attributes(&item.attrs));
try!(self.ann.pre(self, NodeItem(item)));
match item.node {
ast::ItemExternCrate(ref optional_path) => {
try!(self.head(&visibility_qualified(item.vis,
"extern crate")));
if let Some(p) = *optional_path {
let val = token::get_name(p);
if val.contains("-") {
try!(self.print_string(&val, ast::CookedStr));
} else {
try!(self.print_name(p));
}
try!(space(&mut self.s));
try!(word(&mut self.s, "as"));
try!(space(&mut self.s));
}
try!(self.print_ident(item.ident));
try!(word(&mut self.s, ";"));
try!(self.end()); // end inner head-block
try!(self.end()); // end outer head-block
}
ast::ItemUse(ref vp) => {
try!(self.head(&visibility_qualified(item.vis,
"use")));
try!(self.print_view_path(&**vp));
try!(word(&mut self.s, ";"));
try!(self.end()); // end inner head-block
try!(self.end()); // end outer head-block
}
ast::ItemStatic(ref ty, m, ref expr) => {
try!(self.head(&visibility_qualified(item.vis,
"static")));
if m == ast::MutMutable {
try!(self.word_space("mut"));
}
try!(self.print_ident(item.ident));
try!(self.word_space(":"));
try!(self.print_type(&**ty));
try!(space(&mut self.s));
try!(self.end()); // end the head-ibox
try!(self.word_space("="));
try!(self.print_expr(&**expr));
try!(word(&mut self.s, ";"));
try!(self.end()); // end the outer cbox
}
ast::ItemConst(ref ty, ref expr) => {
try!(self.head(&visibility_qualified(item.vis,
"const")));
try!(self.print_ident(item.ident));
try!(self.word_space(":"));
try!(self.print_type(&**ty));
try!(space(&mut self.s));
try!(self.end()); // end the head-ibox
try!(self.word_space("="));
try!(self.print_expr(&**expr));
try!(word(&mut self.s, ";"));
try!(self.end()); // end the outer cbox
}
ast::ItemFn(ref decl, unsafety, constness, abi, ref typarams, ref body) => {
try!(self.head(""));
try!(self.print_fn(
decl,
unsafety,
constness,
abi,
Some(item.ident),
typarams,
None,
item.vis
));
try!(word(&mut self.s, " "));
try!(self.print_block_with_attrs(&**body, &item.attrs));
}
ast::ItemMod(ref _mod) => {
try!(self.head(&visibility_qualified(item.vis,
"mod")));
try!(self.print_ident(item.ident));
try!(self.nbsp());
try!(self.bopen());
try!(self.print_mod(_mod, &item.attrs));
try!(self.bclose(item.span));
}
ast::ItemForeignMod(ref nmod) => {
try!(self.head("extern"));
try!(self.word_nbsp(&nmod.abi.to_string()));
try!(self.bopen());
try!(self.print_foreign_mod(nmod, &item.attrs));
try!(self.bclose(item.span));
}
ast::ItemTy(ref ty, ref params) => {
try!(self.ibox(indent_unit));
try!(self.ibox(0));
try!(self.word_nbsp(&visibility_qualified(item.vis, "type")));
try!(self.print_ident(item.ident));
try!(self.print_generics(params));
try!(self.end()); // end the inner ibox
try!(self.print_where_clause(&params.where_clause));
try!(space(&mut self.s));
try!(self.word_space("="));
try!(self.print_type(&**ty));
try!(word(&mut self.s, ";"));
try!(self.end()); // end the outer ibox
}
ast::ItemEnum(ref enum_definition, ref params) => {
try!(self.print_enum_def(
enum_definition,
params,
item.ident,
item.span,
item.vis
));
}
ast::ItemStruct(ref struct_def, ref generics) => {
try!(self.head(&visibility_qualified(item.vis,"struct")));
try!(self.print_struct(&**struct_def, generics, item.ident, item.span));
}
ast::ItemDefaultImpl(unsafety, ref trait_ref) => {
try!(self.head(""));
try!(self.print_visibility(item.vis));
try!(self.print_unsafety(unsafety));
try!(self.word_nbsp("impl"));
try!(self.print_trait_ref(trait_ref));
try!(space(&mut self.s));
try!(self.word_space("for"));
try!(self.word_space(".."));
try!(self.bopen());
try!(self.bclose(item.span));
}
ast::ItemImpl(unsafety,
polarity,
ref generics,
ref opt_trait,
ref ty,
ref impl_items) => {
try!(self.head(""));
try!(self.print_visibility(item.vis));
try!(self.print_unsafety(unsafety));
try!(self.word_nbsp("impl"));
if generics.is_parameterized() {
try!(self.print_generics(generics));
try!(space(&mut self.s));
}
match polarity {
ast::ImplPolarity::Negative => {
try!(word(&mut self.s, "!"));
},
_ => {}
}
match opt_trait {
&Some(ref t) => {
try!(self.print_trait_ref(t));
try!(space(&mut self.s));
try!(self.word_space("for"));
}
&None => {}
}
try!(self.print_type(&**ty));
try!(self.print_where_clause(&generics.where_clause));
try!(space(&mut self.s));
try!(self.bopen());
try!(self.print_inner_attributes(&item.attrs));
for impl_item in impl_items {
try!(self.print_impl_item(impl_item));
}
try!(self.bclose(item.span));
}
ast::ItemTrait(unsafety, ref generics, ref bounds, ref trait_items) => {
try!(self.head(""));
try!(self.print_visibility(item.vis));
try!(self.print_unsafety(unsafety));
try!(self.word_nbsp("trait"));
try!(self.print_ident(item.ident));
try!(self.print_generics(generics));
let mut real_bounds = Vec::with_capacity(bounds.len());
for b in bounds.iter() {
if let TraitTyParamBound(ref ptr, ast::TraitBoundModifier::Maybe) = *b {
try!(space(&mut self.s));
try!(self.word_space("for ?"));
try!(self.print_trait_ref(&ptr.trait_ref));
} else {
real_bounds.push(b.clone());
}
}
try!(self.print_bounds(":", &real_bounds[..]));
try!(self.print_where_clause(&generics.where_clause));
try!(word(&mut self.s, " "));
try!(self.bopen());
for trait_item in trait_items {
try!(self.print_trait_item(trait_item));
}
try!(self.bclose(item.span));
}
// I think it's reasonable to hide the context here:
ast::ItemMac(codemap::Spanned { node: ast::MacInvocTT(ref pth, ref tts, _),
..}) => {
try!(self.print_visibility(item.vis));
try!(self.print_path(pth, false, 0));
try!(word(&mut self.s, "! "));
try!(self.print_ident(item.ident));
try!(self.cbox(indent_unit));
try!(self.popen());
try!(self.print_tts(&tts[..]));
try!(self.pclose());
try!(word(&mut self.s, ";"));
try!(self.end());
}
}
self.ann.post(self, NodeItem(item))
}
fn print_trait_ref(&mut self, t: &ast::TraitRef) -> io::Result<()> {
self.print_path(&t.path, false, 0)
}
fn print_formal_lifetime_list(&mut self, lifetimes: &[ast::LifetimeDef]) -> io::Result<()> {
if !lifetimes.is_empty() {
try!(word(&mut self.s, "for<"));
let mut comma = false;
for lifetime_def in lifetimes {
if comma {
try!(self.word_space(","))
}
try!(self.print_lifetime_def(lifetime_def));
comma = true;
}
try!(word(&mut self.s, ">"));
}
Ok(())
}
fn print_poly_trait_ref(&mut self, t: &ast::PolyTraitRef) -> io::Result<()> {
try!(self.print_formal_lifetime_list(&t.bound_lifetimes));
self.print_trait_ref(&t.trait_ref)
}
pub fn print_enum_def(&mut self, enum_definition: &ast::EnumDef,
generics: &ast::Generics, ident: ast::Ident,
span: codemap::Span,
visibility: ast::Visibility) -> io::Result<()> {
try!(self.head(&visibility_qualified(visibility, "enum")));
try!(self.print_ident(ident));
try!(self.print_generics(generics));
try!(self.print_where_clause(&generics.where_clause));
try!(space(&mut self.s));
self.print_variants(&enum_definition.variants, span)
}
pub fn print_variants(&mut self,
variants: &[P<ast::Variant>],
span: codemap::Span) -> io::Result<()> {
try!(self.bopen());
for v in variants {
try!(self.space_if_not_bol());
try!(self.maybe_print_comment(v.span.lo));
try!(self.print_outer_attributes(&v.node.attrs));
try!(self.ibox(indent_unit));
try!(self.print_variant(&**v));
try!(word(&mut self.s, ","));
try!(self.end());
try!(self.maybe_print_trailing_comment(v.span, None));
}
self.bclose(span)
}
pub fn print_visibility(&mut self, vis: ast::Visibility) -> io::Result<()> {
match vis {
ast::Public => self.word_nbsp("pub"),
ast::Inherited => Ok(())
}
}
pub fn print_struct(&mut self,
struct_def: &ast::StructDef,
generics: &ast::Generics,
ident: ast::Ident,
span: codemap::Span) -> io::Result<()> {
try!(self.print_ident(ident));
try!(self.print_generics(generics));
if ast_util::struct_def_is_tuple_like(struct_def) {
if !struct_def.fields.is_empty() {
try!(self.popen());
try!(self.commasep(
Inconsistent, &struct_def.fields,
|s, field| {
match field.node.kind {
ast::NamedField(..) => panic!("unexpected named field"),
ast::UnnamedField(vis) => {
try!(s.print_visibility(vis));
try!(s.maybe_print_comment(field.span.lo));
s.print_type(&*field.node.ty)
}
}
}
));
try!(self.pclose());
}
try!(self.print_where_clause(&generics.where_clause));
try!(word(&mut self.s, ";"));
try!(self.end());
self.end() // close the outer-box
} else {
try!(self.print_where_clause(&generics.where_clause));
try!(self.nbsp());
try!(self.bopen());
try!(self.hardbreak_if_not_bol());
for field in &struct_def.fields {
match field.node.kind {
ast::UnnamedField(..) => panic!("unexpected unnamed field"),
ast::NamedField(ident, visibility) => {
try!(self.hardbreak_if_not_bol());
try!(self.maybe_print_comment(field.span.lo));
try!(self.print_outer_attributes(&field.node.attrs));
try!(self.print_visibility(visibility));
try!(self.print_ident(ident));
try!(self.word_nbsp(":"));
try!(self.print_type(&*field.node.ty));
try!(word(&mut self.s, ","));
}
}
}
self.bclose(span)
}
}
/// This doesn't deserve to be called "pretty" printing, but it should be
/// meaning-preserving. A quick hack that might help would be to look at the
/// spans embedded in the TTs to decide where to put spaces and newlines.
/// But it'd be better to parse these according to the grammar of the
/// appropriate macro, transcribe back into the grammar we just parsed from,
/// and then pretty-print the resulting AST nodes (so, e.g., we print
/// expression arguments as expressions). It can be done! I think.
pub fn print_tt(&mut self, tt: &ast::TokenTree) -> io::Result<()> {
match *tt {
ast::TtToken(_, ref tk) => {
try!(word(&mut self.s, &token_to_string(tk)));
match *tk {
parse::token::DocComment(..) => {
hardbreak(&mut self.s)
}
_ => Ok(())
}
}
ast::TtDelimited(_, ref delimed) => {
try!(word(&mut self.s, &token_to_string(&delimed.open_token())));
try!(space(&mut self.s));
try!(self.print_tts(&delimed.tts));
try!(space(&mut self.s));
word(&mut self.s, &token_to_string(&delimed.close_token()))
},
ast::TtSequence(_, ref seq) => {
try!(word(&mut self.s, "$("));
for tt_elt in &seq.tts {
try!(self.print_tt(tt_elt));
}
try!(word(&mut self.s, ")"));
match seq.separator {
Some(ref tk) => {
try!(word(&mut self.s, &token_to_string(tk)));
}
None => {},
}
match seq.op {
ast::ZeroOrMore => word(&mut self.s, "*"),
ast::OneOrMore => word(&mut self.s, "+"),
}
}
}
}
pub fn print_tts(&mut self, tts: &[ast::TokenTree]) -> io::Result<()> {
try!(self.ibox(0));
let mut suppress_space = false;
for (i, tt) in tts.iter().enumerate() {
if i != 0 && !suppress_space {
try!(space(&mut self.s));
}
try!(self.print_tt(tt));
// There should be no space between the module name and the following `::` in paths,
// otherwise imported macros get re-parsed from crate metadata incorrectly (#20701)
suppress_space = match tt {
&ast::TtToken(_, token::Ident(_, token::ModName)) |
&ast::TtToken(_, token::MatchNt(_, _, _, token::ModName)) |
&ast::TtToken(_, token::SubstNt(_, token::ModName)) => true,
_ => false
}
}
self.end()
}
pub fn print_variant(&mut self, v: &ast::Variant) -> io::Result<()> {
try!(self.print_visibility(v.node.vis));
match v.node.kind {
ast::TupleVariantKind(ref args) => {
try!(self.print_ident(v.node.name));
if !args.is_empty() {
try!(self.popen());
try!(self.commasep(Consistent,
&args[..],
|s, arg| s.print_type(&*arg.ty)));
try!(self.pclose());
}
}
ast::StructVariantKind(ref struct_def) => {
try!(self.head(""));
let generics = ast_util::empty_generics();
try!(self.print_struct(&**struct_def, &generics, v.node.name, v.span));
}
}
match v.node.disr_expr {
Some(ref d) => {
try!(space(&mut self.s));
try!(self.word_space("="));
self.print_expr(&**d)
}
_ => Ok(())
}
}
pub fn print_method_sig(&mut self,
ident: ast::Ident,
m: &ast::MethodSig,
vis: ast::Visibility)
-> io::Result<()> {
self.print_fn(&m.decl,
m.unsafety,
m.constness,
m.abi,
Some(ident),
&m.generics,
Some(&m.explicit_self.node),
vis)
}
pub fn print_trait_item(&mut self, ti: &ast::TraitItem)
-> io::Result<()> {
try!(self.ann.pre(self, NodeSubItem(ti.id)));
try!(self.hardbreak_if_not_bol());
try!(self.maybe_print_comment(ti.span.lo));
try!(self.print_outer_attributes(&ti.attrs));
match ti.node {
ast::ConstTraitItem(ref ty, ref default) => {
try!(self.print_associated_const(ti.ident, &ty,
default.as_ref().map(|expr| &**expr),
ast::Inherited));
}
ast::MethodTraitItem(ref sig, ref body) => {
if body.is_some() {
try!(self.head(""));
}
try!(self.print_method_sig(ti.ident, sig, ast::Inherited));
if let Some(ref body) = *body {
try!(self.nbsp());
try!(self.print_block_with_attrs(body, &ti.attrs));
} else {
try!(word(&mut self.s, ";"));
}
}
ast::TypeTraitItem(ref bounds, ref default) => {
try!(self.print_associated_type(ti.ident, Some(bounds),
default.as_ref().map(|ty| &**ty)));
}
}
self.ann.post(self, NodeSubItem(ti.id))
}
pub fn print_impl_item(&mut self, ii: &ast::ImplItem) -> io::Result<()> {
try!(self.ann.pre(self, NodeSubItem(ii.id)));
try!(self.hardbreak_if_not_bol());
try!(self.maybe_print_comment(ii.span.lo));
try!(self.print_outer_attributes(&ii.attrs));
match ii.node {
ast::ConstImplItem(ref ty, ref expr) => {
try!(self.print_associated_const(ii.ident, &ty, Some(&expr), ii.vis));
}
ast::MethodImplItem(ref sig, ref body) => {
try!(self.head(""));
try!(self.print_method_sig(ii.ident, sig, ii.vis));
try!(self.nbsp());
try!(self.print_block_with_attrs(body, &ii.attrs));
}
ast::TypeImplItem(ref ty) => {
try!(self.print_associated_type(ii.ident, None, Some(ty)));
}
ast::MacImplItem(codemap::Spanned { node: ast::MacInvocTT(ref pth, ref tts, _),
..}) => {
// code copied from ItemMac:
try!(self.print_path(pth, false, 0));
try!(word(&mut self.s, "! "));
try!(self.cbox(indent_unit));
try!(self.popen());
try!(self.print_tts(&tts[..]));
try!(self.pclose());
try!(word(&mut self.s, ";"));
try!(self.end())
}
}
self.ann.post(self, NodeSubItem(ii.id))
}
pub fn print_outer_attributes(&mut self,
attrs: &[ast::Attribute]) -> io::Result<()> {
let mut count = 0;
for attr in attrs {
match attr.node.style {
ast::AttrOuter => {
try!(self.print_attribute(attr));
count += 1;
}
_ => {/* fallthrough */ }
}
}
if count > 0 {
try!(self.hardbreak_if_not_bol());
}
Ok(())
}
pub fn print_inner_attributes(&mut self,
attrs: &[ast::Attribute]) -> io::Result<()> {
let mut count = 0;
for attr in attrs {
match attr.node.style {
ast::AttrInner => {
try!(self.print_attribute(attr));
count += 1;
}
_ => {/* fallthrough */ }
}
}
if count > 0 {
try!(self.hardbreak_if_not_bol());
}
Ok(())
}
pub fn print_attribute(&mut self, attr: &ast::Attribute) -> io::Result<()> {
try!(self.hardbreak_if_not_bol());
try!(self.maybe_print_comment(attr.span.lo));
if attr.node.is_sugared_doc {
word(&mut self.s, &attr.value_str().unwrap())
} else {
match attr.node.style {
ast::AttrInner => try!(word(&mut self.s, "#![")),
ast::AttrOuter => try!(word(&mut self.s, "#[")),
}
try!(self.print_meta_item(&*attr.meta()));
word(&mut self.s, "]")
}
}
pub fn print_stmt(&mut self, st: &ast::Stmt) -> io::Result<()> {
try!(self.maybe_print_comment(st.span.lo));
match st.node {
ast::StmtDecl(ref decl, _) => {
try!(self.print_decl(&**decl));
}
ast::StmtExpr(ref expr, _) => {
try!(self.space_if_not_bol());
try!(self.print_expr(&**expr));
}
ast::StmtSemi(ref expr, _) => {
try!(self.space_if_not_bol());
try!(self.print_expr(&**expr));
try!(word(&mut self.s, ";"));
}
ast::StmtMac(ref mac, style) => {
try!(self.space_if_not_bol());
let delim = match style {
ast::MacStmtWithBraces => token::Brace,
_ => token::Paren
};
try!(self.print_mac(&**mac, delim));
match style {
ast::MacStmtWithBraces => {}
_ => try!(word(&mut self.s, ";")),
}
}
}
if parse::classify::stmt_ends_with_semi(&st.node) {
try!(word(&mut self.s, ";"));
}
self.maybe_print_trailing_comment(st.span, None)
}
pub fn print_block(&mut self, blk: &ast::Block) -> io::Result<()> {
self.print_block_with_attrs(blk, &[])
}
pub fn print_block_unclosed(&mut self, blk: &ast::Block) -> io::Result<()> {
self.print_block_unclosed_indent(blk, indent_unit)
}
pub fn print_block_unclosed_indent(&mut self, blk: &ast::Block,
indented: usize) -> io::Result<()> {
self.print_block_maybe_unclosed(blk, indented, &[], false)
}
pub fn print_block_with_attrs(&mut self,
blk: &ast::Block,
attrs: &[ast::Attribute]) -> io::Result<()> {
self.print_block_maybe_unclosed(blk, indent_unit, attrs, true)
}
pub fn print_block_maybe_unclosed(&mut self,
blk: &ast::Block,
indented: usize,
attrs: &[ast::Attribute],
close_box: bool) -> io::Result<()> {
match blk.rules {
ast::UnsafeBlock(..) => try!(self.word_space("unsafe")),
ast::DefaultBlock => ()
}
try!(self.maybe_print_comment(blk.span.lo));
try!(self.ann.pre(self, NodeBlock(blk)));
try!(self.bopen());
try!(self.print_inner_attributes(attrs));
for st in &blk.stmts {
try!(self.print_stmt(&**st));
}
match blk.expr {
Some(ref expr) => {
try!(self.space_if_not_bol());
try!(self.print_expr(&**expr));
try!(self.maybe_print_trailing_comment(expr.span, Some(blk.span.hi)));
}
_ => ()
}
try!(self.bclose_maybe_open(blk.span, indented, close_box));
self.ann.post(self, NodeBlock(blk))
}
fn print_else(&mut self, els: Option<&ast::Expr>) -> io::Result<()> {
match els {
Some(_else) => {
match _else.node {
// "another else-if"
ast::ExprIf(ref i, ref then, ref e) => {
try!(self.cbox(indent_unit - 1));
try!(self.ibox(0));
try!(word(&mut self.s, " else if "));
try!(self.print_expr(&**i));
try!(space(&mut self.s));
try!(self.print_block(&**then));
self.print_else(e.as_ref().map(|e| &**e))
}
// "another else-if-let"
ast::ExprIfLet(ref pat, ref expr, ref then, ref e) => {
try!(self.cbox(indent_unit - 1));
try!(self.ibox(0));
try!(word(&mut self.s, " else if let "));
try!(self.print_pat(&**pat));
try!(space(&mut self.s));
try!(self.word_space("="));
try!(self.print_expr(&**expr));
try!(space(&mut self.s));
try!(self.print_block(&**then));
self.print_else(e.as_ref().map(|e| &**e))
}
// "final else"
ast::ExprBlock(ref b) => {
try!(self.cbox(indent_unit - 1));
try!(self.ibox(0));
try!(word(&mut self.s, " else "));
self.print_block(&**b)
}
// BLEAH, constraints would be great here
_ => {
panic!("print_if saw if with weird alternative");
}
}
}
_ => Ok(())
}
}
pub fn print_if(&mut self, test: &ast::Expr, blk: &ast::Block,
elseopt: Option<&ast::Expr>) -> io::Result<()> {
try!(self.head("if"));
try!(self.print_expr(test));
try!(space(&mut self.s));
try!(self.print_block(blk));
self.print_else(elseopt)
}
pub fn print_if_let(&mut self, pat: &ast::Pat, expr: &ast::Expr, blk: &ast::Block,
elseopt: Option<&ast::Expr>) -> io::Result<()> {
try!(self.head("if let"));
try!(self.print_pat(pat));
try!(space(&mut self.s));
try!(self.word_space("="));
try!(self.print_expr(expr));
try!(space(&mut self.s));
try!(self.print_block(blk));
self.print_else(elseopt)
}
pub fn print_mac(&mut self, m: &ast::Mac, delim: token::DelimToken)
-> io::Result<()> {
match m.node {
// I think it's reasonable to hide the ctxt here:
ast::MacInvocTT(ref pth, ref tts, _) => {
try!(self.print_path(pth, false, 0));
try!(word(&mut self.s, "!"));
match delim {
token::Paren => try!(self.popen()),
token::Bracket => try!(word(&mut self.s, "[")),
token::Brace => try!(self.bopen()),
}
try!(self.print_tts(tts));
match delim {
token::Paren => self.pclose(),
token::Bracket => word(&mut self.s, "]"),
token::Brace => self.bclose(m.span),
}
}
}
}
fn print_call_post(&mut self, args: &[P<ast::Expr>]) -> io::Result<()> {
try!(self.popen());
try!(self.commasep_exprs(Inconsistent, args));
self.pclose()
}
pub fn print_expr_maybe_paren(&mut self, expr: &ast::Expr) -> io::Result<()> {
let needs_par = needs_parentheses(expr);
if needs_par {
try!(self.popen());
}
try!(self.print_expr(expr));
if needs_par {
try!(self.pclose());
}
Ok(())
}
fn print_expr_box(&mut self,
place: &Option<P<ast::Expr>>,
expr: &ast::Expr) -> io::Result<()> {
try!(word(&mut self.s, "box"));
try!(word(&mut self.s, "("));
try!(place.as_ref().map_or(Ok(()), |e|self.print_expr(&**e)));
try!(self.word_space(")"));
self.print_expr(expr)
}
fn print_expr_vec(&mut self, exprs: &[P<ast::Expr>]) -> io::Result<()> {
try!(self.ibox(indent_unit));
try!(word(&mut self.s, "["));
try!(self.commasep_exprs(Inconsistent, &exprs[..]));
try!(word(&mut self.s, "]"));
self.end()
}
fn print_expr_repeat(&mut self,
element: &ast::Expr,
count: &ast::Expr) -> io::Result<()> {
try!(self.ibox(indent_unit));
try!(word(&mut self.s, "["));
try!(self.print_expr(element));
try!(self.word_space(";"));
try!(self.print_expr(count));
try!(word(&mut self.s, "]"));
self.end()
}
fn print_expr_struct(&mut self,
path: &ast::Path,
fields: &[ast::Field],
wth: &Option<P<ast::Expr>>) -> io::Result<()> {
try!(self.print_path(path, true, 0));
if !(fields.is_empty() && wth.is_none()) {
try!(word(&mut self.s, "{"));
try!(self.commasep_cmnt(
Consistent,
&fields[..],
|s, field| {
try!(s.ibox(indent_unit));
try!(s.print_ident(field.ident.node));
try!(s.word_space(":"));
try!(s.print_expr(&*field.expr));
s.end()
},
|f| f.span));
match *wth {
Some(ref expr) => {
try!(self.ibox(indent_unit));
if !fields.is_empty() {
try!(word(&mut self.s, ","));
try!(space(&mut self.s));
}
try!(word(&mut self.s, ".."));
try!(self.print_expr(&**expr));
try!(self.end());
}
_ => try!(word(&mut self.s, ",")),
}
try!(word(&mut self.s, "}"));
}
Ok(())
}
fn print_expr_tup(&mut self, exprs: &[P<ast::Expr>]) -> io::Result<()> {
try!(self.popen());
try!(self.commasep_exprs(Inconsistent, &exprs[..]));
if exprs.len() == 1 {
try!(word(&mut self.s, ","));
}
self.pclose()
}
fn print_expr_call(&mut self,
func: &ast::Expr,
args: &[P<ast::Expr>]) -> io::Result<()> {
try!(self.print_expr_maybe_paren(func));
self.print_call_post(args)
}
fn print_expr_method_call(&mut self,
ident: ast::SpannedIdent,
tys: &[P<ast::Ty>],
args: &[P<ast::Expr>]) -> io::Result<()> {
let base_args = &args[1..];
try!(self.print_expr(&*args[0]));
try!(word(&mut self.s, "."));
try!(self.print_ident(ident.node));
if !tys.is_empty() {
try!(word(&mut self.s, "::<"));
try!(self.commasep(Inconsistent, tys,
|s, ty| s.print_type(&**ty)));
try!(word(&mut self.s, ">"));
}
self.print_call_post(base_args)
}
fn print_expr_binary(&mut self,
op: ast::BinOp,
lhs: &ast::Expr,
rhs: &ast::Expr) -> io::Result<()> {
try!(self.print_expr(lhs));
try!(space(&mut self.s));
try!(self.word_space(ast_util::binop_to_string(op.node)));
self.print_expr(rhs)
}
fn print_expr_unary(&mut self,
op: ast::UnOp,
expr: &ast::Expr) -> io::Result<()> {
try!(word(&mut self.s, ast_util::unop_to_string(op)));
self.print_expr_maybe_paren(expr)
}
fn print_expr_addr_of(&mut self,
mutability: ast::Mutability,
expr: &ast::Expr) -> io::Result<()> {
try!(word(&mut self.s, "&"));
try!(self.print_mutability(mutability));
self.print_expr_maybe_paren(expr)
}
pub fn print_expr(&mut self, expr: &ast::Expr) -> io::Result<()> {
try!(self.maybe_print_comment(expr.span.lo));
try!(self.ibox(indent_unit));
try!(self.ann.pre(self, NodeExpr(expr)));
match expr.node {
ast::ExprBox(ref place, ref expr) => {
try!(self.print_expr_box(place, &**expr));
}
ast::ExprVec(ref exprs) => {
try!(self.print_expr_vec(&exprs[..]));
}
ast::ExprRepeat(ref element, ref count) => {
try!(self.print_expr_repeat(&**element, &**count));
}
ast::ExprStruct(ref path, ref fields, ref wth) => {
try!(self.print_expr_struct(path, &fields[..], wth));
}
ast::ExprTup(ref exprs) => {
try!(self.print_expr_tup(&exprs[..]));
}
ast::ExprCall(ref func, ref args) => {
try!(self.print_expr_call(&**func, &args[..]));
}
ast::ExprMethodCall(ident, ref tys, ref args) => {
try!(self.print_expr_method_call(ident, &tys[..], &args[..]));
}
ast::ExprBinary(op, ref lhs, ref rhs) => {
try!(self.print_expr_binary(op, &**lhs, &**rhs));
}
ast::ExprUnary(op, ref expr) => {
try!(self.print_expr_unary(op, &**expr));
}
ast::ExprAddrOf(m, ref expr) => {
try!(self.print_expr_addr_of(m, &**expr));
}
ast::ExprLit(ref lit) => {
try!(self.print_literal(&**lit));
}
ast::ExprCast(ref expr, ref ty) => {
try!(self.print_expr(&**expr));
try!(space(&mut self.s));
try!(self.word_space("as"));
try!(self.print_type(&**ty));
}
ast::ExprIf(ref test, ref blk, ref elseopt) => {
try!(self.print_if(&**test, &**blk, elseopt.as_ref().map(|e| &**e)));
}
ast::ExprIfLet(ref pat, ref expr, ref blk, ref elseopt) => {
try!(self.print_if_let(&**pat, &**expr, &** blk, elseopt.as_ref().map(|e| &**e)));
}
ast::ExprWhile(ref test, ref blk, opt_ident) => {
if let Some(ident) = opt_ident {
try!(self.print_ident(ident));
try!(self.word_space(":"));
}
try!(self.head("while"));
try!(self.print_expr(&**test));
try!(space(&mut self.s));
try!(self.print_block(&**blk));
}
ast::ExprWhileLet(ref pat, ref expr, ref blk, opt_ident) => {
if let Some(ident) = opt_ident {
try!(self.print_ident(ident));
try!(self.word_space(":"));
}
try!(self.head("while let"));
try!(self.print_pat(&**pat));
try!(space(&mut self.s));
try!(self.word_space("="));
try!(self.print_expr(&**expr));
try!(space(&mut self.s));
try!(self.print_block(&**blk));
}
ast::ExprForLoop(ref pat, ref iter, ref blk, opt_ident) => {
if let Some(ident) = opt_ident {
try!(self.print_ident(ident));
try!(self.word_space(":"));
}
try!(self.head("for"));
try!(self.print_pat(&**pat));
try!(space(&mut self.s));
try!(self.word_space("in"));
try!(self.print_expr(&**iter));
try!(space(&mut self.s));
try!(self.print_block(&**blk));
}
ast::ExprLoop(ref blk, opt_ident) => {
if let Some(ident) = opt_ident {
try!(self.print_ident(ident));
try!(self.word_space(":"));
}
try!(self.head("loop"));
try!(space(&mut self.s));
try!(self.print_block(&**blk));
}
ast::ExprMatch(ref expr, ref arms, _) => {
try!(self.cbox(indent_unit));
try!(self.ibox(4));
try!(self.word_nbsp("match"));
try!(self.print_expr(&**expr));
try!(space(&mut self.s));
try!(self.bopen());
for arm in arms {
try!(self.print_arm(arm));
}
try!(self.bclose_(expr.span, indent_unit));
}
ast::ExprClosure(capture_clause, ref decl, ref body) => {
try!(self.print_capture_clause(capture_clause));
try!(self.print_fn_block_args(&**decl));
try!(space(&mut self.s));
let default_return = match decl.output {
ast::DefaultReturn(..) => true,
_ => false
};
if !default_return || !body.stmts.is_empty() || body.expr.is_none() {
try!(self.print_block_unclosed(&**body));
} else {
// we extract the block, so as not to create another set of boxes
match body.expr.as_ref().unwrap().node {
ast::ExprBlock(ref blk) => {
try!(self.print_block_unclosed(&**blk));
}
_ => {
// this is a bare expression
try!(self.print_expr(body.expr.as_ref().map(|e| &**e).unwrap()));
try!(self.end()); // need to close a box
}
}
}
// a box will be closed by print_expr, but we didn't want an overall
// wrapper so we closed the corresponding opening. so create an
// empty box to satisfy the close.
try!(self.ibox(0));
}
ast::ExprBlock(ref blk) => {
// containing cbox, will be closed by print-block at }
try!(self.cbox(indent_unit));
// head-box, will be closed by print-block after {
try!(self.ibox(0));
try!(self.print_block(&**blk));
}
ast::ExprAssign(ref lhs, ref rhs) => {
try!(self.print_expr(&**lhs));
try!(space(&mut self.s));
try!(self.word_space("="));
try!(self.print_expr(&**rhs));
}
ast::ExprAssignOp(op, ref lhs, ref rhs) => {
try!(self.print_expr(&**lhs));
try!(space(&mut self.s));
try!(word(&mut self.s, ast_util::binop_to_string(op.node)));
try!(self.word_space("="));
try!(self.print_expr(&**rhs));
}
ast::ExprField(ref expr, id) => {
try!(self.print_expr(&**expr));
try!(word(&mut self.s, "."));
try!(self.print_ident(id.node));
}
ast::ExprTupField(ref expr, id) => {
try!(self.print_expr(&**expr));
try!(word(&mut self.s, "."));
try!(self.print_usize(id.node));
}
ast::ExprIndex(ref expr, ref index) => {
try!(self.print_expr(&**expr));
try!(word(&mut self.s, "["));
try!(self.print_expr(&**index));
try!(word(&mut self.s, "]"));
}
ast::ExprRange(ref start, ref end) => {
if let &Some(ref e) = start {
try!(self.print_expr(&**e));
}
try!(word(&mut self.s, ".."));
if let &Some(ref e) = end {
try!(self.print_expr(&**e));
}
}
ast::ExprPath(None, ref path) => {
try!(self.print_path(path, true, 0))
}
ast::ExprPath(Some(ref qself), ref path) => {
try!(self.print_qpath(path, qself, true))
}
ast::ExprBreak(opt_ident) => {
try!(word(&mut self.s, "break"));
try!(space(&mut self.s));
if let Some(ident) = opt_ident {
try!(self.print_ident(ident));
try!(space(&mut self.s));
}
}
ast::ExprAgain(opt_ident) => {
try!(word(&mut self.s, "continue"));
try!(space(&mut self.s));
if let Some(ident) = opt_ident {
try!(self.print_ident(ident));
try!(space(&mut self.s))
}
}
ast::ExprRet(ref result) => {
try!(word(&mut self.s, "return"));
match *result {
Some(ref expr) => {
try!(word(&mut self.s, " "));
try!(self.print_expr(&**expr));
}
_ => ()
}
}
ast::ExprInlineAsm(ref a) => {
try!(word(&mut self.s, "asm!"));
try!(self.popen());
try!(self.print_string(&a.asm, a.asm_str_style));
try!(self.word_space(":"));
try!(self.commasep(Inconsistent, &a.outputs,
|s, &(ref co, ref o, is_rw)| {
match co.slice_shift_char() {
Some(('=', operand)) if is_rw => {
try!(s.print_string(&format!("+{}", operand),
ast::CookedStr))
}
_ => try!(s.print_string(&co, ast::CookedStr))
}
try!(s.popen());
try!(s.print_expr(&**o));
try!(s.pclose());
Ok(())
}));
try!(space(&mut self.s));
try!(self.word_space(":"));
try!(self.commasep(Inconsistent, &a.inputs,
|s, &(ref co, ref o)| {
try!(s.print_string(&co, ast::CookedStr));
try!(s.popen());
try!(s.print_expr(&**o));
try!(s.pclose());
Ok(())
}));
try!(space(&mut self.s));
try!(self.word_space(":"));
try!(self.commasep(Inconsistent, &a.clobbers,
|s, co| {
try!(s.print_string(&co, ast::CookedStr));
Ok(())
}));
let mut options = vec!();
if a.volatile {
options.push("volatile");
}
if a.alignstack {
options.push("alignstack");
}
if a.dialect == ast::AsmDialect::AsmIntel {
options.push("intel");
}
if !options.is_empty() {
try!(space(&mut self.s));
try!(self.word_space(":"));
try!(self.commasep(Inconsistent, &*options,
|s, &co| {
try!(s.print_string(co, ast::CookedStr));
Ok(())
}));
}
try!(self.pclose());
}
ast::ExprMac(ref m) => try!(self.print_mac(m, token::Paren)),
ast::ExprParen(ref e) => {
try!(self.popen());
try!(self.print_expr(&**e));
try!(self.pclose());
}
}
try!(self.ann.post(self, NodeExpr(expr)));
self.end()
}
pub fn print_local_decl(&mut self, loc: &ast::Local) -> io::Result<()> {
try!(self.print_pat(&*loc.pat));
if let Some(ref ty) = loc.ty {
try!(self.word_space(":"));
try!(self.print_type(&**ty));
}
Ok(())
}
pub fn print_decl(&mut self, decl: &ast::Decl) -> io::Result<()> {
try!(self.maybe_print_comment(decl.span.lo));
match decl.node {
ast::DeclLocal(ref loc) => {
try!(self.space_if_not_bol());
try!(self.ibox(indent_unit));
try!(self.word_nbsp("let"));
try!(self.ibox(indent_unit));
try!(self.print_local_decl(&**loc));
try!(self.end());
if let Some(ref init) = loc.init {
try!(self.nbsp());
try!(self.word_space("="));
try!(self.print_expr(&**init));
}
self.end()
}
ast::DeclItem(ref item) => self.print_item(&**item)
}
}
pub fn print_ident(&mut self, ident: ast::Ident) -> io::Result<()> {
try!(word(&mut self.s, &token::get_ident(ident)));
self.ann.post(self, NodeIdent(&ident))
}
pub fn print_usize(&mut self, i: usize) -> io::Result<()> {
word(&mut self.s, &i.to_string())
}
pub fn print_name(&mut self, name: ast::Name) -> io::Result<()> {
try!(word(&mut self.s, &token::get_name(name)));
self.ann.post(self, NodeName(&name))
}
pub fn print_for_decl(&mut self, loc: &ast::Local,
coll: &ast::Expr) -> io::Result<()> {
try!(self.print_local_decl(loc));
try!(space(&mut self.s));
try!(self.word_space("in"));
self.print_expr(coll)
}
fn print_path(&mut self,
path: &ast::Path,
colons_before_params: bool,
depth: usize)
-> io::Result<()>
{
try!(self.maybe_print_comment(path.span.lo));
let mut first = !path.global;
for segment in &path.segments[..path.segments.len()-depth] {
if first {
first = false
} else {
try!(word(&mut self.s, "::"))
}
try!(self.print_ident(segment.identifier));
try!(self.print_path_parameters(&segment.parameters, colons_before_params));
}
Ok(())
}
fn print_qpath(&mut self,
path: &ast::Path,
qself: &ast::QSelf,
colons_before_params: bool)
-> io::Result<()>
{
try!(word(&mut self.s, "<"));
try!(self.print_type(&qself.ty));
if qself.position > 0 {
try!(space(&mut self.s));
try!(self.word_space("as"));
let depth = path.segments.len() - qself.position;
try!(self.print_path(&path, false, depth));
}
try!(word(&mut self.s, ">"));
try!(word(&mut self.s, "::"));
let item_segment = path.segments.last().unwrap();
try!(self.print_ident(item_segment.identifier));
self.print_path_parameters(&item_segment.parameters, colons_before_params)
}
fn print_path_parameters(&mut self,
parameters: &ast::PathParameters,
colons_before_params: bool)
-> io::Result<()>
{
if parameters.is_empty() {
return Ok(());
}
if colons_before_params {
try!(word(&mut self.s, "::"))
}
match *parameters {
ast::AngleBracketedParameters(ref data) => {
try!(word(&mut self.s, "<"));
let mut comma = false;
for lifetime in &data.lifetimes {
if comma {
try!(self.word_space(","))
}
try!(self.print_lifetime(lifetime));
comma = true;
}
if !data.types.is_empty() {
if comma {
try!(self.word_space(","))
}
try!(self.commasep(
Inconsistent,
&data.types,
|s, ty| s.print_type(&**ty)));
comma = true;
}
for binding in &*data.bindings {
if comma {
try!(self.word_space(","))
}
try!(self.print_ident(binding.ident));
try!(space(&mut self.s));
try!(self.word_space("="));
try!(self.print_type(&*binding.ty));
comma = true;
}
try!(word(&mut self.s, ">"))
}
ast::ParenthesizedParameters(ref data) => {
try!(word(&mut self.s, "("));
try!(self.commasep(
Inconsistent,
&data.inputs,
|s, ty| s.print_type(&**ty)));
try!(word(&mut self.s, ")"));
match data.output {
None => { }
Some(ref ty) => {
try!(self.space_if_not_bol());
try!(self.word_space("->"));
try!(self.print_type(&**ty));
}
}
}
}
Ok(())
}
pub fn print_pat(&mut self, pat: &ast::Pat) -> io::Result<()> {
try!(self.maybe_print_comment(pat.span.lo));
try!(self.ann.pre(self, NodePat(pat)));
/* Pat isn't normalized, but the beauty of it
is that it doesn't matter */
match pat.node {
ast::PatWild(ast::PatWildSingle) => try!(word(&mut self.s, "_")),
ast::PatWild(ast::PatWildMulti) => try!(word(&mut self.s, "..")),
ast::PatIdent(binding_mode, ref path1, ref sub) => {
match binding_mode {
ast::BindByRef(mutbl) => {
try!(self.word_nbsp("ref"));
try!(self.print_mutability(mutbl));
}
ast::BindByValue(ast::MutImmutable) => {}
ast::BindByValue(ast::MutMutable) => {
try!(self.word_nbsp("mut"));
}
}
try!(self.print_ident(path1.node));
match *sub {
Some(ref p) => {
try!(word(&mut self.s, "@"));
try!(self.print_pat(&**p));
}
None => ()
}
}
ast::PatEnum(ref path, ref args_) => {
try!(self.print_path(path, true, 0));
match *args_ {
None => try!(word(&mut self.s, "(..)")),
Some(ref args) => {
if !args.is_empty() {
try!(self.popen());
try!(self.commasep(Inconsistent, &args[..],
|s, p| s.print_pat(&**p)));
try!(self.pclose());
}
}
}
}
ast::PatQPath(ref qself, ref path) => {
try!(self.print_qpath(path, qself, false));
}
ast::PatStruct(ref path, ref fields, etc) => {
try!(self.print_path(path, true, 0));
try!(self.nbsp());
try!(self.word_space("{"));
try!(self.commasep_cmnt(
Consistent, &fields[..],
|s, f| {
try!(s.cbox(indent_unit));
if !f.node.is_shorthand {
try!(s.print_ident(f.node.ident));
try!(s.word_nbsp(":"));
}
try!(s.print_pat(&*f.node.pat));
s.end()
},
|f| f.node.pat.span));
if etc {
if !fields.is_empty() { try!(self.word_space(",")); }
try!(word(&mut self.s, ".."));
}
try!(space(&mut self.s));
try!(word(&mut self.s, "}"));
}
ast::PatTup(ref elts) => {
try!(self.popen());
try!(self.commasep(Inconsistent,
&elts[..],
|s, p| s.print_pat(&**p)));
if elts.len() == 1 {
try!(word(&mut self.s, ","));
}
try!(self.pclose());
}
ast::PatBox(ref inner) => {
try!(word(&mut self.s, "box "));
try!(self.print_pat(&**inner));
}
ast::PatRegion(ref inner, mutbl) => {
try!(word(&mut self.s, "&"));
if mutbl == ast::MutMutable {
try!(word(&mut self.s, "mut "));
}
try!(self.print_pat(&**inner));
}
ast::PatLit(ref e) => try!(self.print_expr(&**e)),
ast::PatRange(ref begin, ref end) => {
try!(self.print_expr(&**begin));
try!(space(&mut self.s));
try!(word(&mut self.s, "..."));
try!(self.print_expr(&**end));
}
ast::PatVec(ref before, ref slice, ref after) => {
try!(word(&mut self.s, "["));
try!(self.commasep(Inconsistent,
&before[..],
|s, p| s.print_pat(&**p)));
if let Some(ref p) = *slice {
if !before.is_empty() { try!(self.word_space(",")); }
try!(self.print_pat(&**p));
match **p {
ast::Pat { node: ast::PatWild(ast::PatWildMulti), .. } => {
// this case is handled by print_pat
}
_ => try!(word(&mut self.s, "..")),
}
if !after.is_empty() { try!(self.word_space(",")); }
}
try!(self.commasep(Inconsistent,
&after[..],
|s, p| s.print_pat(&**p)));
try!(word(&mut self.s, "]"));
}
ast::PatMac(ref m) => try!(self.print_mac(m, token::Paren)),
}
self.ann.post(self, NodePat(pat))
}
fn print_arm(&mut self, arm: &ast::Arm) -> io::Result<()> {
// I have no idea why this check is necessary, but here it
// is :(
if arm.attrs.is_empty() {
try!(space(&mut self.s));
}
try!(self.cbox(indent_unit));
try!(self.ibox(0));
try!(self.print_outer_attributes(&arm.attrs));
let mut first = true;
for p in &arm.pats {
if first {
first = false;
} else {
try!(space(&mut self.s));
try!(self.word_space("|"));
}
try!(self.print_pat(&**p));
}
try!(space(&mut self.s));
if let Some(ref e) = arm.guard {
try!(self.word_space("if"));
try!(self.print_expr(&**e));
try!(space(&mut self.s));
}
try!(self.word_space("=>"));
match arm.body.node {
ast::ExprBlock(ref blk) => {
// the block will close the pattern's ibox
try!(self.print_block_unclosed_indent(&**blk, indent_unit));
// If it is a user-provided unsafe block, print a comma after it
if let ast::UnsafeBlock(ast::UserProvided) = blk.rules {
try!(word(&mut self.s, ","));
}
}
_ => {
try!(self.end()); // close the ibox for the pattern
try!(self.print_expr(&*arm.body));
try!(word(&mut self.s, ","));
}
}
self.end() // close enclosing cbox
}
// Returns whether it printed anything
fn print_explicit_self(&mut self,
explicit_self: &ast::ExplicitSelf_,
mutbl: ast::Mutability) -> io::Result<bool> {
try!(self.print_mutability(mutbl));
match *explicit_self {
ast::SelfStatic => { return Ok(false); }
ast::SelfValue(_) => {
try!(word(&mut self.s, "self"));
}
ast::SelfRegion(ref lt, m, _) => {
try!(word(&mut self.s, "&"));
try!(self.print_opt_lifetime(lt));
try!(self.print_mutability(m));
try!(word(&mut self.s, "self"));
}
ast::SelfExplicit(ref typ, _) => {
try!(word(&mut self.s, "self"));
try!(self.word_space(":"));
try!(self.print_type(&**typ));
}
}
return Ok(true);
}
pub fn print_fn(&mut self,
decl: &ast::FnDecl,
unsafety: ast::Unsafety,
constness: ast::Constness,
abi: abi::Abi,
name: Option<ast::Ident>,
generics: &ast::Generics,
opt_explicit_self: Option<&ast::ExplicitSelf_>,
vis: ast::Visibility) -> io::Result<()> {
try!(self.print_fn_header_info(unsafety, constness, abi, vis));
if let Some(name) = name {
try!(self.nbsp());
try!(self.print_ident(name));
}
try!(self.print_generics(generics));
try!(self.print_fn_args_and_ret(decl, opt_explicit_self));
self.print_where_clause(&generics.where_clause)
}
pub fn print_fn_args(&mut self, decl: &ast::FnDecl,
opt_explicit_self: Option<&ast::ExplicitSelf_>)
-> io::Result<()> {
// It is unfortunate to duplicate the commasep logic, but we want the
// self type and the args all in the same box.
try!(self.rbox(0, Inconsistent));
let mut first = true;
if let Some(explicit_self) = opt_explicit_self {
let m = match explicit_self {
&ast::SelfStatic => ast::MutImmutable,
_ => match decl.inputs[0].pat.node {
ast::PatIdent(ast::BindByValue(m), _, _) => m,
_ => ast::MutImmutable
}
};
first = !try!(self.print_explicit_self(explicit_self, m));
}
// HACK(eddyb) ignore the separately printed self argument.
let args = if first {
&decl.inputs[..]
} else {
&decl.inputs[1..]
};
for arg in args {
if first { first = false; } else { try!(self.word_space(",")); }
try!(self.print_arg(arg));
}
self.end()
}
pub fn print_fn_args_and_ret(&mut self, decl: &ast::FnDecl,
opt_explicit_self: Option<&ast::ExplicitSelf_>)
-> io::Result<()> {
try!(self.popen());
try!(self.print_fn_args(decl, opt_explicit_self));
if decl.variadic {
try!(word(&mut self.s, ", ..."));
}
try!(self.pclose());
self.print_fn_output(decl)
}
pub fn print_fn_block_args(
&mut self,
decl: &ast::FnDecl)
-> io::Result<()> {
try!(word(&mut self.s, "|"));
try!(self.print_fn_args(decl, None));
try!(word(&mut self.s, "|"));
if let ast::DefaultReturn(..) = decl.output {
return Ok(());
}
try!(self.space_if_not_bol());
try!(self.word_space("->"));
match decl.output {
ast::Return(ref ty) => {
try!(self.print_type(&**ty));
self.maybe_print_comment(ty.span.lo)
}
ast::DefaultReturn(..) => unreachable!(),
ast::NoReturn(span) => {
try!(self.word_nbsp("!"));
self.maybe_print_comment(span.lo)
}
}
}
pub fn print_capture_clause(&mut self, capture_clause: ast::CaptureClause)
-> io::Result<()> {
match capture_clause {
ast::CaptureByValue => self.word_space("move"),
ast::CaptureByRef => Ok(()),
}
}
pub fn print_bounds(&mut self,
prefix: &str,
bounds: &[ast::TyParamBound])
-> io::Result<()> {
if !bounds.is_empty() {
try!(word(&mut self.s, prefix));
let mut first = true;
for bound in bounds {
try!(self.nbsp());
if first {
first = false;
} else {
try!(self.word_space("+"));
}
try!(match *bound {
TraitTyParamBound(ref tref, TraitBoundModifier::None) => {
self.print_poly_trait_ref(tref)
}
TraitTyParamBound(ref tref, TraitBoundModifier::Maybe) => {
try!(word(&mut self.s, "?"));
self.print_poly_trait_ref(tref)
}
RegionTyParamBound(ref lt) => {
self.print_lifetime(lt)
}
})
}
Ok(())
} else {
Ok(())
}
}
pub fn print_lifetime(&mut self,
lifetime: &ast::Lifetime)
-> io::Result<()>
{
self.print_name(lifetime.name)
}
pub fn print_lifetime_def(&mut self,
lifetime: &ast::LifetimeDef)
-> io::Result<()>
{
try!(self.print_lifetime(&lifetime.lifetime));
let mut sep = ":";
for v in &lifetime.bounds {
try!(word(&mut self.s, sep));
try!(self.print_lifetime(v));
sep = "+";
}
Ok(())
}
pub fn print_generics(&mut self,
generics: &ast::Generics)
-> io::Result<()>
{
let total = generics.lifetimes.len() + generics.ty_params.len();
if total == 0 {
return Ok(());
}
try!(word(&mut self.s, "<"));
let mut ints = Vec::new();
for i in 0..total {
ints.push(i);
}
try!(self.commasep(Inconsistent, &ints[..], |s, &idx| {
if idx < generics.lifetimes.len() {
let lifetime = &generics.lifetimes[idx];
s.print_lifetime_def(lifetime)
} else {
let idx = idx - generics.lifetimes.len();
let param = &generics.ty_params[idx];
s.print_ty_param(param)
}
}));
try!(word(&mut self.s, ">"));
Ok(())
}
pub fn print_ty_param(&mut self, param: &ast::TyParam) -> io::Result<()> {
try!(self.print_ident(param.ident));
try!(self.print_bounds(":", &param.bounds));
match param.default {
Some(ref default) => {
try!(space(&mut self.s));
try!(self.word_space("="));
self.print_type(&**default)
}
_ => Ok(())
}
}
pub fn print_where_clause(&mut self, where_clause: &ast::WhereClause)
-> io::Result<()> {
if where_clause.predicates.is_empty() {
return Ok(())
}
try!(space(&mut self.s));
try!(self.word_space("where"));
for (i, predicate) in where_clause.predicates.iter().enumerate() {
if i != 0 {
try!(self.word_space(","));
}
match predicate {
&ast::WherePredicate::BoundPredicate(ast::WhereBoundPredicate{ref bound_lifetimes,
ref bounded_ty,
ref bounds,
..}) => {
try!(self.print_formal_lifetime_list(bound_lifetimes));
try!(self.print_type(&**bounded_ty));
try!(self.print_bounds(":", bounds));
}
&ast::WherePredicate::RegionPredicate(ast::WhereRegionPredicate{ref lifetime,
ref bounds,
..}) => {
try!(self.print_lifetime(lifetime));
try!(word(&mut self.s, ":"));
for (i, bound) in bounds.iter().enumerate() {
try!(self.print_lifetime(bound));
if i != 0 {
try!(word(&mut self.s, ":"));
}
}
}
&ast::WherePredicate::EqPredicate(ast::WhereEqPredicate{ref path, ref ty, ..}) => {
try!(self.print_path(path, false, 0));
try!(space(&mut self.s));
try!(self.word_space("="));
try!(self.print_type(&**ty));
}
}
}
Ok(())
}
pub fn print_meta_item(&mut self, item: &ast::MetaItem) -> io::Result<()> {
try!(self.ibox(indent_unit));
match item.node {
ast::MetaWord(ref name) => {
try!(word(&mut self.s, &name));
}
ast::MetaNameValue(ref name, ref value) => {
try!(self.word_space(&name[..]));
try!(self.word_space("="));
try!(self.print_literal(value));
}
ast::MetaList(ref name, ref items) => {
try!(word(&mut self.s, &name));
try!(self.popen());
try!(self.commasep(Consistent,
&items[..],
|s, i| s.print_meta_item(&**i)));
try!(self.pclose());
}
}
self.end()
}
pub fn print_view_path(&mut self, vp: &ast::ViewPath) -> io::Result<()> {
match vp.node {
ast::ViewPathSimple(ident, ref path) => {
try!(self.print_path(path, false, 0));
// FIXME(#6993) can't compare identifiers directly here
if path.segments.last().unwrap().identifier.name !=
ident.name {
try!(space(&mut self.s));
try!(self.word_space("as"));
try!(self.print_ident(ident));
}
Ok(())
}
ast::ViewPathGlob(ref path) => {
try!(self.print_path(path, false, 0));
word(&mut self.s, "::*")
}
ast::ViewPathList(ref path, ref idents) => {
if path.segments.is_empty() {
try!(word(&mut self.s, "{"));
} else {
try!(self.print_path(path, false, 0));
try!(word(&mut self.s, "::{"));
}
try!(self.commasep(Inconsistent, &idents[..], |s, w| {
match w.node {
ast::PathListIdent { name, .. } => {
s.print_ident(name)
},
ast::PathListMod { .. } => {
word(&mut s.s, "self")
}
}
}));
word(&mut self.s, "}")
}
}
}
pub fn print_mutability(&mut self,
mutbl: ast::Mutability) -> io::Result<()> {
match mutbl {
ast::MutMutable => self.word_nbsp("mut"),
ast::MutImmutable => Ok(()),
}
}
pub fn print_mt(&mut self, mt: &ast::MutTy) -> io::Result<()> {
try!(self.print_mutability(mt.mutbl));
self.print_type(&*mt.ty)
}
pub fn print_arg(&mut self, input: &ast::Arg) -> io::Result<()> {
try!(self.ibox(indent_unit));
match input.ty.node {
ast::TyInfer => try!(self.print_pat(&*input.pat)),
_ => {
match input.pat.node {
ast::PatIdent(_, ref path1, _) if
path1.node.name ==
parse::token::special_idents::invalid.name => {
// Do nothing.
}
_ => {
try!(self.print_pat(&*input.pat));
try!(word(&mut self.s, ":"));
try!(space(&mut self.s));
}
}
try!(self.print_type(&*input.ty));
}
}
self.end()
}
pub fn print_fn_output(&mut self, decl: &ast::FnDecl) -> io::Result<()> {
if let ast::DefaultReturn(..) = decl.output {
return Ok(());
}
try!(self.space_if_not_bol());
try!(self.ibox(indent_unit));
try!(self.word_space("->"));
match decl.output {
ast::NoReturn(_) =>
try!(self.word_nbsp("!")),
ast::DefaultReturn(..) => unreachable!(),
ast::Return(ref ty) =>
try!(self.print_type(&**ty))
}
try!(self.end());
match decl.output {
ast::Return(ref output) => self.maybe_print_comment(output.span.lo),
_ => Ok(())
}
}
pub fn print_ty_fn(&mut self,
abi: abi::Abi,
unsafety: ast::Unsafety,
decl: &ast::FnDecl,
name: Option<ast::Ident>,
generics: &ast::Generics,
opt_explicit_self: Option<&ast::ExplicitSelf_>)
-> io::Result<()> {
try!(self.ibox(indent_unit));
if !generics.lifetimes.is_empty() || !generics.ty_params.is_empty() {
try!(word(&mut self.s, "for"));
try!(self.print_generics(generics));
}
let generics = ast::Generics {
lifetimes: Vec::new(),
ty_params: OwnedSlice::empty(),
where_clause: ast::WhereClause {
id: ast::DUMMY_NODE_ID,
predicates: Vec::new(),
},
};
try!(self.print_fn(decl,
unsafety,
ast::Constness::NotConst,
abi,
name,
generics,
opt_explicit_self,
ast::Inherited));
self.end()
}
pub fn maybe_print_trailing_comment(&mut self, span: codemap::Span,
next_pos: Option<BytePos>)
-> io::Result<()> {
let cm = match self.cm {
Some(cm) => cm,
_ => return Ok(())
};
match self.next_comment() {
Some(ref cmnt) => {
if (*cmnt).style != comments::Trailing { return Ok(()) }
let span_line = cm.lookup_char_pos(span.hi);
let comment_line = cm.lookup_char_pos((*cmnt).pos);
let mut next = (*cmnt).pos + BytePos(1);
match next_pos { None => (), Some(p) => next = p }
if span.hi < (*cmnt).pos && (*cmnt).pos < next &&
span_line.line == comment_line.line {
try!(self.print_comment(cmnt));
self.cur_cmnt_and_lit.cur_cmnt += 1;
}
}
_ => ()
}
Ok(())
}
pub fn print_remaining_comments(&mut self) -> io::Result<()> {
// If there aren't any remaining comments, then we need to manually
// make sure there is a line break at the end.
if self.next_comment().is_none() {
try!(hardbreak(&mut self.s));
}
loop {
match self.next_comment() {
Some(ref cmnt) => {
try!(self.print_comment(cmnt));
self.cur_cmnt_and_lit.cur_cmnt += 1;
}
_ => break
}
}
Ok(())
}
pub fn print_literal(&mut self, lit: &ast::Lit) -> io::Result<()> {
try!(self.maybe_print_comment(lit.span.lo));
match self.next_lit(lit.span.lo) {
Some(ref ltrl) => {
return word(&mut self.s, &(*ltrl).lit);
}
_ => ()
}
match lit.node {
ast::LitStr(ref st, style) => self.print_string(&st, style),
ast::LitByte(byte) => {
let mut res = String::from("b'");
res.extend(ascii::escape_default(byte).map(|c| c as char));
res.push('\'');
word(&mut self.s, &res[..])
}
ast::LitChar(ch) => {
let mut res = String::from("'");
res.extend(ch.escape_default());
res.push('\'');
word(&mut self.s, &res[..])
}
ast::LitInt(i, t) => {
match t {
ast::SignedIntLit(st, ast::Plus) => {
word(&mut self.s,
&ast_util::int_ty_to_string(st, Some(i as i64)))
}
ast::SignedIntLit(st, ast::Minus) => {
let istr = ast_util::int_ty_to_string(st, Some(-(i as i64)));
word(&mut self.s,
&format!("-{}", istr))
}
ast::UnsignedIntLit(ut) => {
word(&mut self.s, &ast_util::uint_ty_to_string(ut, Some(i)))
}
ast::UnsuffixedIntLit(ast::Plus) => {
word(&mut self.s, &format!("{}", i))
}
ast::UnsuffixedIntLit(ast::Minus) => {
word(&mut self.s, &format!("-{}", i))
}
}
}
ast::LitFloat(ref f, t) => {
word(&mut self.s,
&format!(
"{}{}",
&f,
&ast_util::float_ty_to_string(t)))
}
ast::LitFloatUnsuffixed(ref f) => word(&mut self.s, &f[..]),
ast::LitBool(val) => {
if val { word(&mut self.s, "true") } else { word(&mut self.s, "false") }
}
ast::LitBinary(ref v) => {
let mut escaped: String = String::new();
for &ch in &**v {
escaped.extend(ascii::escape_default(ch)
.map(|c| c as char));
}
word(&mut self.s, &format!("b\"{}\"", escaped))
}
}
}
pub fn next_lit(&mut self, pos: BytePos) -> Option<comments::Literal> {
match self.literals {
Some(ref lits) => {
while self.cur_cmnt_and_lit.cur_lit < lits.len() {
let ltrl = (*lits)[self.cur_cmnt_and_lit.cur_lit].clone();
if ltrl.pos > pos { return None; }
self.cur_cmnt_and_lit.cur_lit += 1;
if ltrl.pos == pos { return Some(ltrl); }
}
None
}
_ => None
}
}
pub fn maybe_print_comment(&mut self, pos: BytePos) -> io::Result<()> {
loop {
match self.next_comment() {
Some(ref cmnt) => {
if (*cmnt).pos < pos {
try!(self.print_comment(cmnt));
self.cur_cmnt_and_lit.cur_cmnt += 1;
} else { break; }
}
_ => break
}
}
Ok(())
}
pub fn print_comment(&mut self,
cmnt: &comments::Comment) -> io::Result<()> {
match cmnt.style {
comments::Mixed => {
assert_eq!(cmnt.lines.len(), 1);
try!(zerobreak(&mut self.s));
try!(word(&mut self.s, &cmnt.lines[0]));
zerobreak(&mut self.s)
}
comments::Isolated => {
try!(self.hardbreak_if_not_bol());
for line in &cmnt.lines {
// Don't print empty lines because they will end up as trailing
// whitespace
if !line.is_empty() {
try!(word(&mut self.s, &line[..]));
}
try!(hardbreak(&mut self.s));
}
Ok(())
}
comments::Trailing => {
try!(word(&mut self.s, " "));
if cmnt.lines.len() == 1 {
try!(word(&mut self.s, &cmnt.lines[0]));
hardbreak(&mut self.s)
} else {
try!(self.ibox(0));
for line in &cmnt.lines {
if !line.is_empty() {
try!(word(&mut self.s, &line[..]));
}
try!(hardbreak(&mut self.s));
}
self.end()
}
}
comments::BlankLine => {
// We need to do at least one, possibly two hardbreaks.
let is_semi = match self.s.last_token() {
pp::Token::String(s, _) => ";" == s,
_ => false
};
if is_semi || self.is_begin() || self.is_end() {
try!(hardbreak(&mut self.s));
}
hardbreak(&mut self.s)
}
}
}
pub fn print_string(&mut self, st: &str,
style: ast::StrStyle) -> io::Result<()> {
let st = match style {
ast::CookedStr => {
(format!("\"{}\"", st.escape_default()))
}
ast::RawStr(n) => {
(format!("r{delim}\"{string}\"{delim}",
delim=repeat("#", n),
string=st))
}
};
word(&mut self.s, &st[..])
}
pub fn next_comment(&mut self) -> Option<comments::Comment> {
match self.comments {
Some(ref cmnts) => {
if self.cur_cmnt_and_lit.cur_cmnt < cmnts.len() {
Some(cmnts[self.cur_cmnt_and_lit.cur_cmnt].clone())
} else {
None
}
}
_ => None
}
}
pub fn print_opt_abi_and_extern_if_nondefault(&mut self,
opt_abi: Option<abi::Abi>)
-> io::Result<()> {
match opt_abi {
Some(abi::Rust) => Ok(()),
Some(abi) => {
try!(self.word_nbsp("extern"));
self.word_nbsp(&abi.to_string())
}
None => Ok(())
}
}
pub fn print_extern_opt_abi(&mut self,
opt_abi: Option<abi::Abi>) -> io::Result<()> {
match opt_abi {
Some(abi) => {
try!(self.word_nbsp("extern"));
self.word_nbsp(&abi.to_string())
}
None => Ok(())
}
}
pub fn print_fn_header_info(&mut self,
unsafety: ast::Unsafety,
constness: ast::Constness,
abi: abi::Abi,
vis: ast::Visibility) -> io::Result<()> {
try!(word(&mut self.s, &visibility_qualified(vis, "")));
try!(self.print_unsafety(unsafety));
match constness {
ast::Constness::NotConst => {}
ast::Constness::Const => try!(self.word_nbsp("unsafe"))
}
if abi != abi::Rust {
try!(self.word_nbsp("extern"));
try!(self.word_nbsp(&abi.to_string()));
}
word(&mut self.s, "fn")
}
pub fn print_unsafety(&mut self, s: ast::Unsafety) -> io::Result<()> {
match s {
ast::Unsafety::Normal => Ok(()),
ast::Unsafety::Unsafe => self.word_nbsp("unsafe"),
}
}
}
fn repeat(s: &str, n: usize) -> String { iter::repeat(s).take(n).collect() }
#[cfg(test)]
mod tests {
use super::*;
use ast;
use ast_util;
use codemap;
use parse::token;
#[test]
fn test_fun_to_string() {
let abba_ident = token::str_to_ident("abba");
let decl = ast::FnDecl {
inputs: Vec::new(),
output: ast::DefaultReturn(codemap::DUMMY_SP),
variadic: false
};
let generics = ast_util::empty_generics();
assert_eq!(fun_to_string(&decl, ast::Unsafety::Normal,
ast::Constness::NotConst,
abba_ident,
None, &generics),
"fn abba()");
}
#[test]
fn test_variant_to_string() {
let ident = token::str_to_ident("principal_skinner");
let var = codemap::respan(codemap::DUMMY_SP, ast::Variant_ {
name: ident,
attrs: Vec::new(),
// making this up as I go.... ?
kind: ast::TupleVariantKind(Vec::new()),
id: 0,
disr_expr: None,
vis: ast::Public,
});
let varstr = variant_to_string(&var);
assert_eq!(varstr, "pub principal_skinner");
}
#[test]
fn test_signed_int_to_string() {
let pos_int = ast::LitInt(42, ast::SignedIntLit(ast::TyI32, ast::Plus));
let neg_int = ast::LitInt((!42 + 1) as u64, ast::SignedIntLit(ast::TyI32, ast::Minus));
assert_eq!(format!("-{}", lit_to_string(&codemap::dummy_spanned(pos_int))),
lit_to_string(&codemap::dummy_spanned(neg_int)));
}
}