diff options
Diffstat (limited to 'src/libsyntax/parse')
| -rw-r--r-- | src/libsyntax/parse/parser/pat.rs | 41 |
1 files changed, 21 insertions, 20 deletions
diff --git a/src/libsyntax/parse/parser/pat.rs b/src/libsyntax/parse/parser/pat.rs index 5c53a497ff4..b821d9da354 100644 --- a/src/libsyntax/parse/parser/pat.rs +++ b/src/libsyntax/parse/parser/pat.rs @@ -202,26 +202,10 @@ impl<'a> Parser<'a> { } else { // Try to parse everything else as literal with optional minus match self.parse_literal_maybe_minus() { - Ok(begin) => { - let op_span = self.token.span; - if self.check(&token::DotDot) || self.check(&token::DotDotEq) || - self.check(&token::DotDotDot) { - let (end_kind, form) = if self.eat(&token::DotDotDot) { - (RangeEnd::Included(RangeSyntax::DotDotDot), "...") - } else if self.eat(&token::DotDotEq) { - (RangeEnd::Included(RangeSyntax::DotDotEq), "..=") - } else if self.eat(&token::DotDot) { - (RangeEnd::Excluded, "..") - } else { - panic!("impossible case: we already matched \ - on a range-operator token") - }; - let end = self.parse_pat_range_end_opt(&begin, form)?; - PatKind::Range(begin, end, respan(op_span, end_kind)) - } else { - PatKind::Lit(begin) - } - } + Ok(begin) if self.check(&token::DotDot) || self.check(&token::DotDotEq) + || self.check(&token::DotDotDot) + => self.parse_pat_range_starting_with_lit(begin)?, + Ok(begin) => PatKind::Lit(begin), Err(mut err) => { self.cancel(&mut err); let expected = expected.unwrap_or("pattern"); @@ -360,6 +344,23 @@ impl<'a> Parser<'a> { Ok(PatKind::Range(begin, end, respan(op_span, end_kind))) } + /// Parse a range pattern `$literal $form $end?` where `$form = ".." | "..." | "..=" ;`. + /// The `$path` has already been parsed and the next token is the `$form`. + fn parse_pat_range_starting_with_lit(&mut self, begin: P<Expr>) -> PResult<'a, PatKind> { + let op_span = self.token.span; + let (end_kind, form) = if self.eat(&token::DotDotDot) { + (RangeEnd::Included(RangeSyntax::DotDotDot), "...") + } else if self.eat(&token::DotDotEq) { + (RangeEnd::Included(RangeSyntax::DotDotEq), "..=") + } else if self.eat(&token::DotDot) { + (RangeEnd::Excluded, "..") + } else { + panic!("impossible case: we already matched on a range-operator token") + }; + let end = self.parse_pat_range_end_opt(&begin, form)?; + Ok(PatKind::Range(begin, end, respan(op_span, end_kind))) + } + // Helper function to decide whether to parse as ident binding // or to try to do something more complex like range patterns. fn parse_as_ident(&mut self) -> bool { |