From: simonpj@microsoft.com <unknown>
Date: Thu, 21 Jun 2007 14:37:21 +0000 (+0000)
Subject: FIX read040: patterns with type sig on LHS of do-binding
X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=commitdiff_plain;h=bb511e2deeb63e4b1a92b033283cd63de3e5a27c

FIX read040: patterns with type sig on LHS of do-binding

f () = do { x :: Bool <- return True; ... }

For some reason the production for 'pat' required 'infixexp' on the
LHS of a do-notation binding.  This patch makes it an 'exp', which
thereby allows an expression with a type sig.

Happily, there are no new shift-reduce errors, so I don't think this
will break anything else.
---

diff --git a/compiler/parser/Parser.y.pp b/compiler/parser/Parser.y.pp
index 82f6474..b31e025 100644
--- a/compiler/parser/Parser.y.pp
+++ b/compiler/parser/Parser.y.pp
@@ -1494,7 +1494,7 @@ gdpat	:: { LGRHS RdrName }
 -- Bangs inside are parsed as infix operator applications, so that
 -- we parse them right when bang-patterns are off
 pat     :: { LPat RdrName }
-pat 	: infixexp		{% checkPattern $1 }
+pat 	:  exp		 	{% checkPattern $1 }
 	| '!' aexp		{% checkPattern (LL (SectionR (L1 (HsVar bang_RDR)) $2)) }
 
 apat   :: { LPat RdrName }