1053 lines
30 KiB
Rust
1053 lines
30 KiB
Rust
import std._io;
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import std.option;
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import std.option.some;
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import std.option.none;
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import std.map.hashmap;
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import driver.session;
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import util.common;
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import util.common.append;
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import util.common.span;
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import util.common.new_str_hash;
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state type parser =
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state obj {
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fn peek() -> token.token;
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impure fn bump();
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impure fn err(str s);
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fn get_session() -> session.session;
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fn get_span() -> common.span;
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fn next_def_id() -> ast.def_id;
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};
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impure fn new_parser(session.session sess,
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ast.crate_num crate, str path) -> parser {
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state obj stdio_parser(session.session sess,
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mutable token.token tok,
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mutable common.pos lo,
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mutable common.pos hi,
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mutable ast.def_num def,
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ast.crate_num crate,
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lexer.reader rdr)
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{
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fn peek() -> token.token {
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// log token.to_str(tok);
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ret tok;
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}
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impure fn bump() {
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tok = lexer.next_token(rdr);
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lo = rdr.get_mark_pos();
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hi = rdr.get_curr_pos();
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}
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impure fn err(str m) {
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auto span = rec(filename = rdr.get_filename(),
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lo = lo, hi = hi);
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sess.span_err(span, m);
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}
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fn get_session() -> session.session {
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ret sess;
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}
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fn get_span() -> common.span {
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ret rec(filename = rdr.get_filename(),
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lo = lo, hi = hi);
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}
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fn next_def_id() -> ast.def_id {
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def += 1;
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ret tup(crate, def);
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}
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}
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auto srdr = _io.new_stdio_reader(path);
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auto rdr = lexer.new_reader(srdr, path);
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auto npos = rdr.get_curr_pos();
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ret stdio_parser(sess, lexer.next_token(rdr),
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npos, npos, 0, crate, rdr);
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}
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impure fn expect(parser p, token.token t) {
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if (p.peek() == t) {
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p.bump();
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} else {
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let str s = "expecting ";
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s += token.to_str(t);
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s += ", found ";
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s += token.to_str(p.peek());
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p.err(s);
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}
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}
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fn spanned[T](&span lo, &span hi, &T node) -> ast.spanned[T] {
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ret rec(node=node, span=rec(filename=lo.filename,
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lo=lo.lo,
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hi=hi.hi));
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}
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impure fn parse_ident(parser p) -> ast.ident {
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alt (p.peek()) {
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case (token.IDENT(?i)) { p.bump(); ret i; }
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case (_) {
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p.err("expecting ident");
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fail;
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}
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}
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}
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impure fn parse_possibly_mutable_ty(parser p) -> tup(bool, @ast.ty) {
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auto mut;
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if (p.peek() == token.MUTABLE) {
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p.bump();
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mut = true;
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} else {
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mut = false;
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}
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ret tup(mut, parse_ty(p));
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}
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impure fn parse_ty_fn(parser p) -> ast.ty_ {
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impure fn parse_fn_input_ty(parser p) -> rec(ast.mode mode, @ast.ty ty) {
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auto mode;
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if (p.peek() == token.BINOP(token.AND)) {
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p.bump();
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mode = ast.alias;
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} else {
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mode = ast.val;
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}
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auto t = parse_ty(p);
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alt (p.peek()) {
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case (token.IDENT(_)) { p.bump(); /* ignore the param name */ }
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case (_) { /* no param name present */ }
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}
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ret rec(mode=mode, ty=t);
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}
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auto lo = p.get_span();
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expect(p, token.FN);
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auto f = parse_fn_input_ty; // FIXME: trans_const_lval bug
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auto inputs = parse_seq[rec(ast.mode mode, @ast.ty ty)](token.LPAREN,
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token.RPAREN, some(token.COMMA), f, p);
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let @ast.ty output;
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if (p.peek() == token.RARROW) {
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p.bump();
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output = parse_ty(p);
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} else {
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output = @spanned(lo, inputs.span, ast.ty_nil);
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}
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ret ast.ty_fn(inputs.node, output);
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}
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impure fn parse_ty(parser p) -> @ast.ty {
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auto lo = p.get_span();
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auto hi = lo;
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let ast.ty_ t;
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alt (p.peek()) {
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case (token.INT) { p.bump(); t = ast.ty_int; }
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case (token.UINT) { p.bump(); t = ast.ty_int; }
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case (token.STR) { p.bump(); t = ast.ty_str; }
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case (token.CHAR) { p.bump(); t = ast.ty_char; }
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case (token.MACH(?tm)) { p.bump(); t = ast.ty_machine(tm); }
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case (token.LPAREN) {
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p.bump();
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alt (p.peek()) {
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case (token.RPAREN) {
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hi = p.get_span();
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p.bump();
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t = ast.ty_nil;
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}
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case (_) {
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t = parse_ty(p).node;
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hi = p.get_span();
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expect(p, token.RPAREN);
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}
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}
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}
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case (token.AT) { p.bump(); t = ast.ty_box(parse_ty(p)); }
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case (token.VEC) {
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p.bump();
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expect(p, token.LBRACKET);
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t = ast.ty_vec(parse_ty(p));
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hi = p.get_span();
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expect(p, token.RBRACKET);
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}
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case (token.TUP) {
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p.bump();
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auto f = parse_possibly_mutable_ty; // FIXME: trans_const_lval bug
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auto elems = parse_seq[tup(bool, @ast.ty)](token.LPAREN,
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token.RPAREN, some(token.COMMA), f, p);
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hi = p.get_span();
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t = ast.ty_tup(elems.node);
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}
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case (token.FN) {
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t = parse_ty_fn(p);
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alt (t) {
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case (ast.ty_fn(_, ?out)) {
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hi = out.span;
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}
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}
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}
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case (token.IDENT(_)) {
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let ast.path pth = vec();
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let bool more = true;
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while (more) {
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alt (p.peek()) {
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case (token.IDENT(?i)) {
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auto n = parse_name(p, i);
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hi = n.span;
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pth += n;
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if (p.peek() == token.DOT) {
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p.bump();
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} else {
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more = false;
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}
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}
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case (_) {
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more = false;
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}
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}
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}
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t = ast.ty_path(pth, none[ast.def]);
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}
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case (_) {
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p.err("expecting type");
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t = ast.ty_nil;
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fail;
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}
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}
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ret @spanned(lo, hi, t);
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}
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impure fn parse_arg(parser p) -> ast.arg {
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let ast.mode m = ast.val;
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if (p.peek() == token.BINOP(token.AND)) {
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m = ast.alias;
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p.bump();
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}
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let @ast.ty t = parse_ty(p);
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let ast.ident i = parse_ident(p);
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ret rec(mode=m, ty=t, ident=i, id=p.next_def_id());
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}
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impure fn parse_seq[T](token.token bra,
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token.token ket,
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option.t[token.token] sep,
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(impure fn(parser) -> T) f,
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parser p) -> util.common.spanned[vec[T]] {
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let bool first = true;
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auto lo = p.get_span();
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expect(p, bra);
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let vec[T] v = vec();
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while (p.peek() != ket) {
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alt(sep) {
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case (some[token.token](?t)) {
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if (first) {
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first = false;
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} else {
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expect(p, t);
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}
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}
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case (_) {
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}
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}
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// FIXME: v += f(p) doesn't work at the moment.
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let T t = f(p);
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v += vec(t);
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}
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auto hi = p.get_span();
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expect(p, ket);
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ret spanned(lo, hi, v);
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}
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impure fn parse_lit(parser p) -> option.t[ast.lit] {
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auto lo = p.get_span();
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let ast.lit_ lit;
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alt (p.peek()) {
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case (token.LIT_INT(?i)) {
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p.bump();
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lit = ast.lit_int(i);
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}
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case (token.LIT_UINT(?u)) {
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p.bump();
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lit = ast.lit_uint(u);
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}
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case (token.LIT_CHAR(?c)) {
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p.bump();
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lit = ast.lit_char(c);
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}
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case (token.LIT_BOOL(?b)) {
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p.bump();
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lit = ast.lit_bool(b);
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}
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case (token.LIT_STR(?s)) {
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p.bump();
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lit = ast.lit_str(s);
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}
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case (_) {
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lit = ast.lit_nil; // FIXME: typestate bug requires this
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ret none[ast.lit];
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}
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}
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ret some(spanned(lo, lo, lit));
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}
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impure fn parse_name(parser p, ast.ident id) -> ast.name {
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auto lo = p.get_span();
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p.bump();
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let vec[@ast.ty] v = vec();
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let util.common.spanned[vec[@ast.ty]] tys = rec(node=v, span=lo);
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alt (p.peek()) {
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case (token.LBRACKET) {
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auto pf = parse_ty;
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tys = parse_seq[@ast.ty](token.LBRACKET,
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token.RBRACKET,
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some(token.COMMA),
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pf, p);
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}
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case (_) {
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}
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}
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ret spanned(lo, tys.span, rec(ident=id, types=tys.node));
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}
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impure fn parse_possibly_mutable_expr(parser p) -> tup(bool, @ast.expr) {
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auto mut;
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if (p.peek() == token.MUTABLE) {
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p.bump();
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mut = true;
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} else {
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mut = false;
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}
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ret tup(mut, parse_expr(p));
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}
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impure fn parse_bottom_expr(parser p) -> @ast.expr {
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auto lo = p.get_span();
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auto hi = lo;
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// FIXME: can only remove this sort of thing when both typestate and
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// alt-exhaustive-match checking are co-operating.
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auto lit = @spanned(lo, lo, ast.lit_nil);
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let ast.expr_ ex = ast.expr_lit(lit, ast.ann_none);
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alt (p.peek()) {
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case (token.IDENT(?i)) {
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auto n = parse_name(p, i);
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hi = n.span;
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ex = ast.expr_name(n, none[ast.def], ast.ann_none);
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alt (p.peek()) {
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case (token.LPAREN) {
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// Call expr.
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auto pf = parse_expr;
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auto es = parse_seq[@ast.expr](token.LPAREN,
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token.RPAREN,
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some(token.COMMA),
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pf, p);
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ex = ast.expr_call(@spanned(lo, hi, ex),
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es.node, ast.ann_none);
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hi = es.span;
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}
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}
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}
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case (token.LPAREN) {
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p.bump();
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alt (p.peek()) {
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case (token.RPAREN) {
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hi = p.get_span();
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p.bump();
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auto lit = @spanned(lo, hi, ast.lit_nil);
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ret @spanned(lo, hi,
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ast.expr_lit(lit, ast.ann_none));
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}
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}
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auto e = parse_expr(p);
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hi = p.get_span();
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expect(p, token.RPAREN);
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ret @spanned(lo, hi, e.node);
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}
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case (token.TUP) {
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p.bump();
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auto pf = parse_possibly_mutable_expr;
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auto es = parse_seq[tup(bool, @ast.expr)](token.LPAREN,
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token.RPAREN,
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some(token.COMMA),
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pf, p);
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hi = es.span;
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ex = ast.expr_tup(es.node, ast.ann_none);
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}
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case (token.VEC) {
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p.bump();
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auto pf = parse_expr;
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auto es = parse_seq[@ast.expr](token.LPAREN,
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token.RPAREN,
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some(token.COMMA),
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pf, p);
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hi = es.span;
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ex = ast.expr_vec(es.node, ast.ann_none);
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}
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case (token.REC) {
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p.bump();
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impure fn parse_entry(parser p) ->
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tup(ast.ident, @ast.expr) {
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auto i = parse_ident(p);
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expect(p, token.EQ);
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auto e = parse_expr(p);
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ret tup(i, e);
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}
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auto pf = parse_entry;
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auto es =
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parse_seq[tup(ast.ident, @ast.expr)](token.LPAREN,
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token.RPAREN,
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some(token.COMMA),
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pf, p);
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hi = es.span;
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ex = ast.expr_rec(es.node, ast.ann_none);
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}
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case (_) {
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alt (parse_lit(p)) {
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case (some[ast.lit](?lit)) {
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hi = lit.span;
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ex = ast.expr_lit(@lit, ast.ann_none);
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}
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case (none[ast.lit]) {
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p.err("expecting expression");
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}
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}
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}
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}
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ret @spanned(lo, hi, ex);
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}
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impure fn parse_path_expr(parser p) -> @ast.expr {
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auto lo = p.get_span();
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auto e = parse_bottom_expr(p);
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auto hi = e.span;
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while (true) {
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alt (p.peek()) {
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case (token.DOT) {
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p.bump();
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alt (p.peek()) {
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case (token.IDENT(?i)) {
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hi = p.get_span();
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p.bump();
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auto e_ = ast.expr_field(e, i, ast.ann_none);
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e = @spanned(lo, hi, e_);
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}
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case (token.LPAREN) {
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p.bump();
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auto ix = parse_bottom_expr(p);
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hi = ix.span;
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auto e_ = ast.expr_index(e, ix, ast.ann_none);
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e = @spanned(lo, hi, e_);
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}
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}
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}
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case (_) {
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ret e;
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}
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}
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}
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ret e;
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}
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impure fn parse_prefix_expr(parser p) -> @ast.expr {
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auto lo = p.get_span();
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auto hi = lo;
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// FIXME: can only remove this sort of thing when both typestate and
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// alt-exhaustive-match checking are co-operating.
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auto lit = @spanned(lo, lo, ast.lit_nil);
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let ast.expr_ ex = ast.expr_lit(lit, ast.ann_none);
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alt (p.peek()) {
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case (token.NOT) {
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p.bump();
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auto e = parse_prefix_expr(p);
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hi = e.span;
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ex = ast.expr_unary(ast.not, e, ast.ann_none);
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}
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case (token.TILDE) {
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p.bump();
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auto e = parse_prefix_expr(p);
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hi = e.span;
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ex = ast.expr_unary(ast.bitnot, e, ast.ann_none);
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}
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case (token.BINOP(?b)) {
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alt (b) {
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case (token.MINUS) {
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p.bump();
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auto e = parse_prefix_expr(p);
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hi = e.span;
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ex = ast.expr_unary(ast.neg, e, ast.ann_none);
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}
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case (token.STAR) {
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p.bump();
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auto e = parse_prefix_expr(p);
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hi = e.span;
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ex = ast.expr_unary(ast.deref, e, ast.ann_none);
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}
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case (_) {
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ret parse_path_expr(p);
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}
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}
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}
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case (token.AT) {
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p.bump();
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auto e = parse_prefix_expr(p);
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hi = e.span;
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ex = ast.expr_unary(ast.box, e, ast.ann_none);
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}
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case (_) {
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ret parse_path_expr(p);
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}
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}
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ret @spanned(lo, hi, ex);
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}
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|
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impure fn parse_binops(parser p,
|
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(impure fn(parser) -> @ast.expr) sub,
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vec[tup(token.binop, ast.binop)] ops)
|
|
-> @ast.expr {
|
|
auto lo = p.get_span();
|
|
auto hi = lo;
|
|
auto e = sub(p);
|
|
auto more = true;
|
|
while (more) {
|
|
more = false;
|
|
for (tup(token.binop, ast.binop) pair in ops) {
|
|
alt (p.peek()) {
|
|
case (token.BINOP(?op)) {
|
|
if (pair._0 == op) {
|
|
p.bump();
|
|
auto rhs = sub(p);
|
|
hi = rhs.span;
|
|
auto exp = ast.expr_binary(pair._1, e, rhs,
|
|
ast.ann_none);
|
|
e = @spanned(lo, hi, exp);
|
|
more = true;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
ret e;
|
|
}
|
|
|
|
impure fn parse_binary_exprs(parser p,
|
|
(impure fn(parser) -> @ast.expr) sub,
|
|
vec[tup(token.token, ast.binop)] ops)
|
|
-> @ast.expr {
|
|
auto lo = p.get_span();
|
|
auto hi = lo;
|
|
auto e = sub(p);
|
|
auto more = true;
|
|
while (more) {
|
|
more = false;
|
|
for (tup(token.token, ast.binop) pair in ops) {
|
|
if (pair._0 == p.peek()) {
|
|
p.bump();
|
|
auto rhs = sub(p);
|
|
hi = rhs.span;
|
|
auto exp = ast.expr_binary(pair._1, e, rhs, ast.ann_none);
|
|
e = @spanned(lo, hi, exp);
|
|
more = true;
|
|
}
|
|
}
|
|
}
|
|
ret e;
|
|
}
|
|
|
|
impure fn parse_factor_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_prefix_expr;
|
|
ret parse_binops(p, sub, vec(tup(token.STAR, ast.mul),
|
|
tup(token.SLASH, ast.div),
|
|
tup(token.PERCENT, ast.rem)));
|
|
}
|
|
|
|
impure fn parse_term_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_factor_expr;
|
|
ret parse_binops(p, sub, vec(tup(token.PLUS, ast.add),
|
|
tup(token.MINUS, ast.sub)));
|
|
}
|
|
|
|
impure fn parse_shift_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_term_expr;
|
|
ret parse_binops(p, sub, vec(tup(token.LSL, ast.lsl),
|
|
tup(token.LSR, ast.lsr),
|
|
tup(token.ASR, ast.asr)));
|
|
}
|
|
|
|
impure fn parse_bitand_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_shift_expr;
|
|
ret parse_binops(p, sub, vec(tup(token.AND, ast.bitand)));
|
|
}
|
|
|
|
impure fn parse_bitxor_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_bitand_expr;
|
|
ret parse_binops(p, sub, vec(tup(token.CARET, ast.bitxor)));
|
|
}
|
|
|
|
impure fn parse_bitor_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_bitxor_expr;
|
|
ret parse_binops(p, sub, vec(tup(token.OR, ast.bitor)));
|
|
}
|
|
|
|
impure fn parse_cast_expr(parser p) -> @ast.expr {
|
|
auto lo = p.get_span();
|
|
auto e = parse_bitor_expr(p);
|
|
auto hi = e.span;
|
|
while (true) {
|
|
alt (p.peek()) {
|
|
case (token.AS) {
|
|
p.bump();
|
|
auto t = parse_ty(p);
|
|
hi = t.span;
|
|
e = @spanned(lo, hi, ast.expr_cast(e, t, ast.ann_none));
|
|
}
|
|
|
|
case (_) {
|
|
ret e;
|
|
}
|
|
}
|
|
}
|
|
ret e;
|
|
}
|
|
|
|
impure fn parse_relational_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_cast_expr;
|
|
ret parse_binary_exprs(p, sub, vec(tup(token.LT, ast.lt),
|
|
tup(token.LE, ast.le),
|
|
tup(token.GE, ast.ge),
|
|
tup(token.GT, ast.gt)));
|
|
}
|
|
|
|
|
|
impure fn parse_equality_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_relational_expr;
|
|
ret parse_binary_exprs(p, sub, vec(tup(token.EQEQ, ast.eq),
|
|
tup(token.NE, ast.ne)));
|
|
}
|
|
|
|
impure fn parse_and_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_equality_expr;
|
|
ret parse_binary_exprs(p, sub, vec(tup(token.ANDAND, ast.and)));
|
|
}
|
|
|
|
impure fn parse_or_expr(parser p) -> @ast.expr {
|
|
auto sub = parse_and_expr;
|
|
ret parse_binary_exprs(p, sub, vec(tup(token.OROR, ast.or)));
|
|
}
|
|
|
|
impure fn parse_assign_expr(parser p) -> @ast.expr {
|
|
auto lo = p.get_span();
|
|
auto lhs = parse_or_expr(p);
|
|
alt (p.peek()) {
|
|
case (token.EQ) {
|
|
p.bump();
|
|
auto rhs = parse_expr(p);
|
|
ret @spanned(lo, rhs.span,
|
|
ast.expr_assign(lhs, rhs, ast.ann_none));
|
|
}
|
|
}
|
|
ret lhs;
|
|
}
|
|
|
|
impure fn parse_if_expr(parser p) -> @ast.expr {
|
|
auto lo = p.get_span();
|
|
auto hi = lo;
|
|
|
|
expect(p, token.IF);
|
|
expect(p, token.LPAREN);
|
|
auto cond = parse_expr(p);
|
|
expect(p, token.RPAREN);
|
|
auto thn = parse_block(p);
|
|
let option.t[ast.block] els = none[ast.block];
|
|
hi = thn.span;
|
|
alt (p.peek()) {
|
|
case (token.ELSE) {
|
|
p.bump();
|
|
auto eblk = parse_block(p);
|
|
els = some(eblk);
|
|
hi = eblk.span;
|
|
}
|
|
}
|
|
ret @spanned(lo, hi, ast.expr_if(cond, thn, els, ast.ann_none));
|
|
}
|
|
|
|
impure fn parse_while_expr(parser p) -> @ast.expr {
|
|
auto lo = p.get_span();
|
|
auto hi = lo;
|
|
|
|
expect(p, token.WHILE);
|
|
expect (p, token.LPAREN);
|
|
auto cond = parse_expr(p);
|
|
expect(p, token.RPAREN);
|
|
auto body = parse_block(p);
|
|
hi = body.span;
|
|
ret @spanned(lo, hi, ast.expr_while(cond, body, ast.ann_none));
|
|
}
|
|
|
|
impure fn parse_do_while_expr(parser p) -> @ast.expr {
|
|
auto lo = p.get_span();
|
|
auto hi = lo;
|
|
|
|
expect(p, token.DO);
|
|
auto body = parse_block(p);
|
|
expect(p, token.WHILE);
|
|
expect (p, token.LPAREN);
|
|
auto cond = parse_expr(p);
|
|
expect(p, token.RPAREN);
|
|
expect(p, token.SEMI);
|
|
hi = cond.span;
|
|
ret @spanned(lo, hi, ast.expr_do_while(body, cond, ast.ann_none));
|
|
}
|
|
|
|
impure fn parse_expr(parser p) -> @ast.expr {
|
|
alt (p.peek()) {
|
|
case (token.LBRACE) {
|
|
auto blk = parse_block(p);
|
|
ret @spanned(blk.span, blk.span,
|
|
ast.expr_block(blk, ast.ann_none));
|
|
}
|
|
case (token.IF) {
|
|
ret parse_if_expr(p);
|
|
}
|
|
case (token.WHILE) {
|
|
ret parse_while_expr(p);
|
|
}
|
|
case (token.DO) {
|
|
ret parse_do_while_expr(p);
|
|
}
|
|
case (_) {
|
|
ret parse_assign_expr(p);
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
impure fn parse_initializer(parser p) -> option.t[@ast.expr] {
|
|
if (p.peek() == token.EQ) {
|
|
p.bump();
|
|
ret some(parse_expr(p));
|
|
}
|
|
|
|
ret none[@ast.expr];
|
|
}
|
|
|
|
impure fn parse_let(parser p) -> @ast.decl {
|
|
auto lo = p.get_span();
|
|
|
|
expect(p, token.LET);
|
|
auto ty = parse_ty(p);
|
|
auto ident = parse_ident(p);
|
|
auto init = parse_initializer(p);
|
|
|
|
auto hi = p.get_span();
|
|
expect(p, token.SEMI);
|
|
|
|
let ast.local local = rec(ty = some(ty),
|
|
infer = false,
|
|
ident = ident,
|
|
init = init,
|
|
id = p.next_def_id(),
|
|
ann = ast.ann_none);
|
|
|
|
ret @spanned(lo, hi, ast.decl_local(@local));
|
|
}
|
|
|
|
impure fn parse_auto(parser p) -> @ast.decl {
|
|
auto lo = p.get_span();
|
|
|
|
expect(p, token.AUTO);
|
|
auto ident = parse_ident(p);
|
|
auto init = parse_initializer(p);
|
|
|
|
auto hi = p.get_span();
|
|
expect(p, token.SEMI);
|
|
|
|
let ast.local local = rec(ty = none[@ast.ty],
|
|
infer = true,
|
|
ident = ident,
|
|
init = init,
|
|
id = p.next_def_id(),
|
|
ann = ast.ann_none);
|
|
|
|
ret @spanned(lo, hi, ast.decl_local(@local));
|
|
}
|
|
|
|
impure fn parse_stmt(parser p) -> @ast.stmt {
|
|
auto lo = p.get_span();
|
|
alt (p.peek()) {
|
|
|
|
case (token.LOG) {
|
|
p.bump();
|
|
auto e = parse_expr(p);
|
|
auto hi = p.get_span();
|
|
expect(p, token.SEMI);
|
|
ret @spanned(lo, hi, ast.stmt_log(e));
|
|
}
|
|
|
|
case (token.CHECK) {
|
|
p.bump();
|
|
alt (p.peek()) {
|
|
case (token.LPAREN) {
|
|
auto e = parse_expr(p);
|
|
auto hi = p.get_span();
|
|
expect(p, token.SEMI);
|
|
ret @spanned(lo, hi, ast.stmt_check_expr(e));
|
|
}
|
|
case (_) {
|
|
p.get_session().unimpl("constraint-check stmt");
|
|
}
|
|
}
|
|
}
|
|
|
|
case (token.RET) {
|
|
p.bump();
|
|
alt (p.peek()) {
|
|
case (token.SEMI) {
|
|
p.bump();
|
|
ret @spanned(lo, p.get_span(),
|
|
ast.stmt_ret(none[@ast.expr]));
|
|
}
|
|
case (_) {
|
|
auto e = parse_expr(p);
|
|
expect(p, token.SEMI);
|
|
ret @spanned(lo, e.span,
|
|
ast.stmt_ret(some[@ast.expr](e)));
|
|
}
|
|
}
|
|
}
|
|
|
|
case (token.LET) {
|
|
auto decl = parse_let(p);
|
|
auto hi = p.get_span();
|
|
ret @spanned(lo, hi, ast.stmt_decl(decl));
|
|
}
|
|
|
|
case (token.AUTO) {
|
|
auto decl = parse_auto(p);
|
|
auto hi = p.get_span();
|
|
ret @spanned(lo, hi, ast.stmt_decl(decl));
|
|
}
|
|
|
|
// Handle the (few) block-expr stmts first.
|
|
|
|
case (token.IF) {
|
|
auto e = parse_expr(p);
|
|
ret @spanned(lo, e.span, ast.stmt_expr(e));
|
|
}
|
|
|
|
case (token.WHILE) {
|
|
auto e = parse_expr(p);
|
|
ret @spanned(lo, e.span, ast.stmt_expr(e));
|
|
}
|
|
|
|
case (token.DO) {
|
|
auto e = parse_expr(p);
|
|
ret @spanned(lo, e.span, ast.stmt_expr(e));
|
|
}
|
|
|
|
case (token.LBRACE) {
|
|
auto e = parse_expr(p);
|
|
ret @spanned(lo, e.span, ast.stmt_expr(e));
|
|
}
|
|
|
|
|
|
// Remainder are line-expr stmts.
|
|
|
|
case (_) {
|
|
auto e = parse_expr(p);
|
|
auto hi = p.get_span();
|
|
expect(p, token.SEMI);
|
|
ret @spanned(lo, hi, ast.stmt_expr(e));
|
|
}
|
|
}
|
|
p.err("expected statement");
|
|
fail;
|
|
}
|
|
|
|
impure fn parse_block(parser p) -> ast.block {
|
|
auto f = parse_stmt;
|
|
// FIXME: passing parse_stmt as an lval doesn't work at the moment.
|
|
auto stmts = parse_seq[@ast.stmt](token.LBRACE,
|
|
token.RBRACE,
|
|
none[token.token],
|
|
f, p);
|
|
auto index = new_str_hash[uint]();
|
|
auto u = 0u;
|
|
for (@ast.stmt s in stmts.node) {
|
|
// FIXME: typestate bug requires we do this up top, not
|
|
// down below loop. Sigh.
|
|
u += 1u;
|
|
alt (s.node) {
|
|
case (ast.stmt_decl(?d)) {
|
|
alt (d.node) {
|
|
case (ast.decl_local(?loc)) {
|
|
index.insert(loc.ident, u-1u);
|
|
}
|
|
case (ast.decl_item(?it)) {
|
|
alt (it.node) {
|
|
case (ast.item_fn(?i, _, _, _)) {
|
|
index.insert(i, u-1u);
|
|
}
|
|
case (ast.item_mod(?i, _, _)) {
|
|
index.insert(i, u-1u);
|
|
}
|
|
case (ast.item_ty(?i, _, _, _)) {
|
|
index.insert(i, u-1u);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
let ast.block_ b = rec(stmts=stmts.node, index=index);
|
|
ret spanned(stmts.span, stmts.span, b);
|
|
}
|
|
|
|
impure fn parse_item_fn(parser p) -> tup(ast.ident, @ast.item) {
|
|
auto lo = p.get_span();
|
|
expect(p, token.FN);
|
|
auto id = parse_ident(p);
|
|
auto pf = parse_arg;
|
|
let util.common.spanned[vec[ast.arg]] inputs =
|
|
// FIXME: passing parse_arg as an lval doesn't work at the
|
|
// moment.
|
|
parse_seq[ast.arg]
|
|
(token.LPAREN,
|
|
token.RPAREN,
|
|
some(token.COMMA),
|
|
pf, p);
|
|
|
|
let @ast.ty output;
|
|
if (p.peek() == token.RARROW) {
|
|
p.bump();
|
|
output = parse_ty(p);
|
|
} else {
|
|
output = @spanned(lo, inputs.span, ast.ty_nil);
|
|
}
|
|
|
|
auto body = parse_block(p);
|
|
|
|
let ast._fn f = rec(inputs = inputs.node,
|
|
output = output,
|
|
body = body);
|
|
|
|
auto item = ast.item_fn(id, f, p.next_def_id(), ast.ann_none);
|
|
ret tup(id, @spanned(lo, body.span, item));
|
|
}
|
|
|
|
impure fn parse_mod_items(parser p, token.token term) -> ast._mod {
|
|
let vec[@ast.item] items = vec();
|
|
let hashmap[ast.ident,uint] index = new_str_hash[uint]();
|
|
let uint u = 0u;
|
|
while (p.peek() != term) {
|
|
auto pair = parse_item(p);
|
|
append[@ast.item](items, pair._1);
|
|
index.insert(pair._0, u);
|
|
u += 1u;
|
|
}
|
|
ret rec(items=items, index=index);
|
|
}
|
|
|
|
impure fn parse_item_mod(parser p) -> tup(ast.ident, @ast.item) {
|
|
auto lo = p.get_span();
|
|
expect(p, token.MOD);
|
|
auto id = parse_ident(p);
|
|
expect(p, token.LBRACE);
|
|
auto m = parse_mod_items(p, token.RBRACE);
|
|
auto hi = p.get_span();
|
|
expect(p, token.RBRACE);
|
|
auto item = ast.item_mod(id, m, p.next_def_id());
|
|
ret tup(id, @spanned(lo, hi, item));
|
|
}
|
|
|
|
impure fn parse_item_type(parser p) -> tup(ast.ident, @ast.item) {
|
|
auto lo = p.get_span();
|
|
expect(p, token.TYPE);
|
|
auto id = parse_ident(p);
|
|
expect(p, token.EQ);
|
|
auto ty = parse_ty(p);
|
|
auto hi = p.get_span();
|
|
expect(p, token.SEMI);
|
|
auto item = ast.item_ty(id, ty, p.next_def_id(), ast.ann_none);
|
|
ret tup(id, @spanned(lo, hi, item));
|
|
}
|
|
|
|
impure fn parse_item(parser p) -> tup(ast.ident, @ast.item) {
|
|
alt (p.peek()) {
|
|
case (token.FN) {
|
|
ret parse_item_fn(p);
|
|
}
|
|
case (token.MOD) {
|
|
ret parse_item_mod(p);
|
|
}
|
|
case (token.TYPE) {
|
|
ret parse_item_type(p);
|
|
}
|
|
case (?t) {
|
|
p.err("expected item but found " + token.to_str(t));
|
|
}
|
|
}
|
|
fail;
|
|
}
|
|
|
|
impure fn parse_crate(parser p) -> @ast.crate {
|
|
auto lo = p.get_span();
|
|
auto hi = lo;
|
|
auto m = parse_mod_items(p, token.EOF);
|
|
ret @spanned(lo, hi, rec(module=m));
|
|
}
|
|
|
|
//
|
|
// Local Variables:
|
|
// mode: rust
|
|
// fill-column: 78;
|
|
// indent-tabs-mode: nil
|
|
// c-basic-offset: 4
|
|
// buffer-file-coding-system: utf-8-unix
|
|
// compile-command: "make -k -C ../.. 2>&1 | sed -e 's/\\/x\\//x:\\//g'";
|
|
// End:
|
|
//
|