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| author | Simon Peyton Jones <simonpj@microsoft.com> | 2012-12-21 17:40:08 +0000 |
|---|---|---|
| committer | Simon Peyton Jones <simonpj@microsoft.com> | 2012-12-21 17:40:08 +0000 |
| commit | e1779a71cf9bdfcac6e9cc8d9eb0b8763060954b (patch) | |
| tree | 1225feae0aa9eb12b8ed322445bbcb6c746fd438 /libraries/base/Text | |
| parent | a18cf9cbdfec08732f5b7e0c886a5d899a6a5998 (diff) | |
| download | haskell-e1779a71cf9bdfcac6e9cc8d9eb0b8763060954b.tar.gz | |
Define GHC.Read.expectP and Text.Read.Lex.expect
They are now used by TcGenDeriv
Diffstat (limited to 'libraries/base/Text')
| -rw-r--r-- | libraries/base/Text/Read/Lex.hs | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/libraries/base/Text/Read/Lex.hs b/libraries/base/Text/Read/Lex.hs index f5a07f1658..8a64e21b80 100644 --- a/libraries/base/Text/Read/Lex.hs +++ b/libraries/base/Text/Read/Lex.hs @@ -22,7 +22,7 @@ module Text.Read.Lex , numberToInteger, numberToRational, numberToRangedRational -- lexer - , lex + , lex, expect , hsLex , lexChar @@ -144,6 +144,11 @@ numberToRational (MkDecimal iPart mFPart mExp) lex :: ReadP Lexeme lex = skipSpaces >> lexToken +expect :: Lexeme -> ReadP () +expect lexeme = do { skipSpaces + ; thing <- lexToken + ; if thing == lexeme then return () else pfail } + hsLex :: ReadP String -- ^ Haskell lexer: returns the lexed string, rather than the lexeme hsLex = do skipSpaces |