diff options
Diffstat (limited to 'compiler/GHC/Data/FastString.hs')
| -rw-r--r-- | compiler/GHC/Data/FastString.hs | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/compiler/GHC/Data/FastString.hs b/compiler/GHC/Data/FastString.hs index 9ed0a38df3..3c52de1fae 100644 --- a/compiler/GHC/Data/FastString.hs +++ b/compiler/GHC/Data/FastString.hs @@ -89,6 +89,7 @@ module GHC.Data.FastString isUnderscoreFS, lexicalCompareFS, uniqCompareFS, + headByteFS, -- ** Outputting hPutFS, @@ -609,6 +610,10 @@ headFS fs | SBS.null $ fs_sbs fs = panic "headFS: Empty FastString" headFS fs = head $ unpackFS fs +-- the first byte of the Modified UTF-8 encoded string +headByteFS :: FastString -> Word8 +headByteFS fs = SBS.index (fs_sbs fs) 0 + consFS :: Char -> FastString -> FastString consFS c fs = mkFastString (c : unpackFS fs) |