rust/src/librustc/middle/astconv_util.rs
2015-02-26 07:21:26 +02:00

79 lines
2.6 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.
/*!
* This module contains a simple utility routine
* used by both `typeck` and `const_eval`.
* Almost certainly this could (and should) be refactored out of existence.
*/
use middle::def;
use middle::ty::{self, Ty};
use syntax::ast;
use util::ppaux::Repr;
pub const NO_REGIONS: uint = 1;
pub const NO_TPS: uint = 2;
pub fn check_path_args(tcx: &ty::ctxt, segments: &[ast::PathSegment], flags: uint) {
for segment in segments {
if (flags & NO_TPS) != 0 {
for typ in segment.parameters.types() {
span_err!(tcx.sess, typ.span, E0109,
"type parameters are not allowed on this type");
break;
}
}
if (flags & NO_REGIONS) != 0 {
for lifetime in segment.parameters.lifetimes() {
span_err!(tcx.sess, lifetime.span, E0110,
"lifetime parameters are not allowed on this type");
break;
}
}
}
}
pub fn prim_ty_to_ty<'tcx>(tcx: &ty::ctxt<'tcx>,
segments: &[ast::PathSegment],
nty: ast::PrimTy)
-> Ty<'tcx> {
check_path_args(tcx, segments, NO_TPS | NO_REGIONS);
match nty {
ast::TyBool => tcx.types.bool,
ast::TyChar => tcx.types.char,
ast::TyInt(it) => ty::mk_mach_int(tcx, it),
ast::TyUint(uit) => ty::mk_mach_uint(tcx, uit),
ast::TyFloat(ft) => ty::mk_mach_float(tcx, ft),
ast::TyStr => ty::mk_str(tcx)
}
}
pub fn ast_ty_to_prim_ty<'tcx>(tcx: &ty::ctxt<'tcx>, ast_ty: &ast::Ty)
-> Option<Ty<'tcx>> {
if let ast::TyPath(None, ref path) = ast_ty.node {
let def = match tcx.def_map.borrow().get(&ast_ty.id) {
None => {
tcx.sess.span_bug(ast_ty.span,
&format!("unbound path {}", path.repr(tcx)))
}
Some(d) => d.full_def()
};
if let def::DefPrimTy(nty) = def {
Some(prim_ty_to_ty(tcx, &path.segments, nty))
} else {
None
}
} else {
None
}
}