X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=docs%2Fusers_guide%2Fusing.xml;h=eedc9e112bb58a875cfe1e58ae2f5cc91ebb6779;hb=dbbc561d4599b647b9256bc893b425556fdb5e84;hp=88f9e5e60080cc91f75c5b7f99e5b801a043eb4c;hpb=0560e796f1d813582e066a5f2bec2684c71df44d;p=ghc-hetmet.git diff --git a/docs/users_guide/using.xml b/docs/users_guide/using.xml index 88f9e5e..eedc9e1 100644 --- a/docs/users_guide/using.xml +++ b/docs/users_guide/using.xml @@ -14,7 +14,7 @@ Options can be specified in three ways: - command-line arguments + Command-line arguments structure, command-line command-linearguments @@ -26,9 +26,9 @@ ghc [argument...] - command-line arguments are either options or file names. + Command-line arguments are either options or file names. - command-line options begin with -. + Command-line options begin with -. They may not be grouped: is different from . Options need not precede filenames: e.g., ghc *.o -o @@ -40,7 +40,7 @@ ghc [argument...] - command line options in source files + Command line options in source files source-file options @@ -81,7 +81,7 @@ module X where It is not recommended to move all the contents of your Makefiles into your source files, but in some circumstances, the OPTIONS_GHC pragma is the Right Thing. (If you - use and have OPTION flags in + use and have OPTION flags in your module, the OPTIONS_GHC will get put into the generated .hc file). @@ -104,8 +104,8 @@ module X where modeoptions - Each of GHC's command line options is classified as either - static or dynamic or + Each of GHC's command line options is classified as + static, dynamic or mode: @@ -113,7 +113,7 @@ module X where Mode flags For example, or . - There may be only a single mode flag on the command line. The + There may only be a single mode flag on the command line. The available modes are listed in . @@ -379,9 +379,9 @@ module X where interfaces, and include files (usually something like /usr/local/lib/ghc-5.04 on Unix). This is the value of - $libdirlibdir - in the package configuration file (see ). + $libdirlibdir + in the package configuration file + (see ). @@ -394,7 +394,7 @@ module X where When given the option, GHC will build a multi-module Haskell program by following - dependencies from a single root module (usually + dependencies from one or more root modules (usually just Main). For example, if your Main module is in a file called Main.hs, you could compile and link the @@ -408,7 +408,7 @@ ghc ––make Main.hs names or module names; GHC will figure out all the modules in the program by following the imports from these initial modules. It will then attempt to compile each module which is out of - date, and finally if there is a Main module, + date, and finally, if there is a Main module, the program will also be linked into an executable. The main advantages to using ghc @@ -503,7 +503,7 @@ olleh The first phase to run is determined by each input-file suffix, and the last phase is determined by a flag. If no - relevant flag is present, then go all the way through linking. + relevant flag is present, then go all the way through to linking. This table summarises: @@ -595,9 +595,7 @@ ghc -c Foo.hs Note: The option -E option runs just the pre-processing passes - of the compiler, dumping the result in a file. Note that this - differs from the previous behaviour of dumping the file to - standard output. + of the compiler, dumping the result in a file. Overriding the default behaviour for a file @@ -821,6 +819,7 @@ ghc -c Foo.hs -W option Provides the standard warnings plus , + , , , and . @@ -828,18 +827,27 @@ ghc -c Foo.hs - : + : - - Turns off all warnings, including the standard ones. + + Turns on all warning options that indicate potentially + suspicious code. The warnings that are + not enabled by + are + , + , + , + , and + . - : + : - - Turns on all warning options. + + Turns off all warnings, including the standard ones and + those that -Wall doesn't enable. @@ -905,6 +913,31 @@ ghc -c Foo.hs + : + + + implicit prelude, warning + Have the compiler warn if the Prelude is implicitly + imported. This happens unless either the Prelude module is + explicitly imported with an import ... Prelude ... + line, or this implicit import is disabled (either by + or a + LANGUAGE NoImplicitPrelude pragma). + + Note that no warning is given for syntax that implicitly + refers to the Prelude, even if + would change whether it refers to the Prelude. + For example, no warning is given when + 368 means + Prelude.fromInteger (368::Prelude.Integer) + (where Prelude refers to the actual Prelude module, + regardless of the imports of the module being compiled). + + This warning is off by default. + + + + : @@ -1025,7 +1058,7 @@ f foo = foo { x = 6 } in the inadvertent cyclic definition let x = ... x ... in. - Consequently, this option does + Consequently, this option will complain about cyclic recursive definitions. @@ -1145,7 +1178,7 @@ f "2" = 2 the MR can give rise to unexpected behaviour, so it can be helpful to have an explicit warning that it is being applied. - This warning is on by default. + This warning is off by default. @@ -1241,7 +1274,7 @@ f "2" = 2 Note that higher optimisation levels cause more cross-module optimisation to be performed, which can have an impact on how much of your program needs to be recompiled when - you change something. This is one reaosn to stick to + you change something. This is one reason to stick to no-optimisation when developing code. @@ -1450,6 +1483,50 @@ f "2" = 2 + + + + + Turn off the "state hack" whereby any lambda with a + State# token as argument is considered to be + single-entry, hence it is considered OK to inline things inside + it. This can improve performance of IO and ST monad code, but it + runs the risk of reducing sharing. + + + + + + + + + + Tells GHC to omit all inessential information from the interface file + generated for the module being compiled (say M). This means that a module + importing M will see only the types of the functions that M exports, but not + their unfoldings, strictness info, etc. Hence, for example, + no function exported by M will be inlined + into an importing module. The benefit is that modules that import M will + need to be recompiled less often (only when M's exports change their type, + not when they change their implementation). + + + + + + + + + + + Tells GHC to ignore all inessential information when reading interface files. + That is, even if M.hi contains unfolding or strictness information + for a function, GHC will ignore that information. + + + + + : strict constructor fields @@ -1472,7 +1549,7 @@ f "2" = 2 - + @@ -1490,7 +1567,7 @@ f "2" = 2 - : + : inlining, controlling unfolding, controlling @@ -1516,7 +1593,7 @@ f "2" = 2 - : + inlining, controlling