bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

syntax: Relax path grammar

Browse source
This commit is contained in:
Vadim Petrochenkov 2017-07-29 04:47:12 +03:00
parent 13d94d5fa8
commit 7d21f21f71
5 changed files with 20 additions and 32 deletions
Download patch file Download diff file Expand all files Collapse all files

15
src/libsyntax/parse/parser.rs
View file

@ -84,7 +84,7 @@ pub enum PathStyle {
Expr,
/// In other contexts, notably in types, no ambiguity exists and paths can be written
/// without the disambiguator, e.g. `x<y>` - unambiguously a path.
/// Paths with disambiguators are rejected for now, but may be allowed in the future.
/// Paths with disambiguators are still accepted, `x::<Y>` - unambiguously a path too.
Type,
/// A path with generic arguments disallowed, e.g. `foo::bar::Baz`, used in imports,
/// visibilities or attributes.
@ -1835,18 +1835,7 @@ impl<'a> Parser<'a> {
&& self.look_ahead(1, |t| is_args_start(t)) {
// Generic arguments are found - `<`, `(`, `::<` or `::(`.
let lo = self.span;
if self.eat(&token::ModSep) {
// These errors are not strictly necessary and may be removed in the future.
if style == PathStyle::Type {
let mut err = self.diagnostic().struct_span_err(self.prev_span,
"unnecessary path disambiguator");
err.span_label(self.prev_span, "try removing `::`");
err.emit();
} else if self.token == token::OpenDelim(token::Paren) {
self.diagnostic().span_err(self.prev_span,
"`::` is not supported before parenthesized generic arguments")
}
}
self.eat(&token::ModSep);
let parameters = if self.eat_lt() {
// `<'a, T, A = U>`