X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=docs%2Fusers_guide%2Fusing.xml;h=a4c673cbe4965318e450b9ce4a5f82ba581312c5;hb=56aaa78a63ab27c40a6834ed28ff3f32d1ede214;hp=7ef2f2f99409d11386795e6fd33516696f994e21;hpb=a7554688338b04ec362bc475b0992ef8799c8bd0;p=ghc-hetmet.git diff --git a/docs/users_guide/using.xml b/docs/users_guide/using.xml index 7ef2f2f..a4c673c 100644 --- a/docs/users_guide/using.xml +++ b/docs/users_guide/using.xml @@ -1175,6 +1175,21 @@ foreign import "&f" f :: FunPtr t + : + + + Causes the compiler to emit a warning when a Prelude numeric + conversion converts a type T to the same type T; such calls + are probably no-ops and can be omitted. The functions checked for + are: toInteger, + toRational, + fromIntegral, + and realToFrac. + + + + + : @@ -1206,14 +1221,15 @@ foreign import "&f" f :: FunPtr t incomplete patterns, warning patterns, incomplete - Similarly for incomplete patterns, the function - g below will fail when applied to + Similarly for incomplete patterns, the functions + g and h below will fail when applied to non-empty lists, so the compiler will emit a warning about this when is enabled. g [] = 2 +h = \[] -> 2 This option isn't enabled by default because it can be @@ -1398,6 +1414,7 @@ f "2" = 2 e.g., the ‘default default’ for Haskell 1.4 caused the otherwise unconstrained value 1 to be given the type Int, whereas Haskell 98 + and later defaults it to Integer. This may lead to differences in performance and behaviour, hence the usefulness of being non-silent about this. @@ -1630,31 +1647,6 @@ f "2" = 2 . - - - - : - -Ofile <file> option - optimising, customised - - - (NOTE: not supported since GHC 4.x. Please ask if - you're interested in this.) - - For those who need absolute - control over exactly what options are - used (e.g., compiler writers, sometimes :-), a list of - options can be put in a file and then slurped in with - . - - In that file, comments are of the - #-to-end-of-line variety; blank - lines and most whitespace is ignored. - - Please ask if you are baffled and would like an - example of ! - - We don't use a flag for day-to-day