X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=docs%2Fusers_guide%2Fghci.xml;h=5daa29c9a12eb6faf5d9c6db5834e449bd9c5baa;hb=878ce92d0559e10a083b6983f2d23380086026d8;hp=bac55ed4312bdc72b594bf507d34779af4ad5e79;hpb=6a65049a2b80e42ec44ebd775be98a70101ac495;p=ghc-hetmet.git
diff --git a/docs/users_guide/ghci.xml b/docs/users_guide/ghci.xml
index bac55ed..5daa29c 100644
--- a/docs/users_guide/ghci.xml
+++ b/docs/users_guide/ghci.xml
@@ -611,7 +611,7 @@ Prelude IO>
- The :main command
+ The :main and :run commands
When a program is compiled and executed, it can use the
@@ -636,6 +636,37 @@ Prelude> :main foo bar
["foo","bar"]
+
+ We can also quote arguments which contains characters like
+ spaces, and they are treated like Haskell strings, or we can
+ just use Haskell list syntax:
+
+
+
+Prelude> :main foo "bar baz"
+["foo","bar baz"]
+Prelude> :main ["foo", "bar baz"]
+["foo","bar baz"]
+
+
+
+ Finally, other functions can be called, either with the
+ -main-is flag or the :run
+ command:
+
+
+
+Prelude> let foo = putStrLn "foo" >> System.Environment.getArgs >>= print
+Prelude> let bar = putStrLn "bar" >> System.Environment.getArgs >>= print
+Prelude> :set -main-is foo
+Prelude> :main foo "bar baz"
+foo
+["foo","bar baz"]
+Prelude> :run bar ["foo", "bar baz"]
+bar
+["foo","bar baz"]
+
+
@@ -1437,7 +1468,7 @@ as = 'b' : 'c' : (_t1::[Char])
import Prelude hiding (map)
-map :: (a->b) -> a -> b
+map :: (a->b) -> [a] -> [b]
map f [] = []
map f (x:xs) = f x : map f xs
@@ -1740,6 +1771,32 @@ $ ghci -lm
The !-form also annotates the listing
with comments giving possible imports for each group of
entries.
+
+Prelude> :browse! Data.Maybe
+-- not currently imported
+Data.Maybe.catMaybes :: [Maybe a] -> [a]
+Data.Maybe.fromJust :: Maybe a -> a
+Data.Maybe.fromMaybe :: a -> Maybe a -> a
+Data.Maybe.isJust :: Maybe a -> Bool
+Data.Maybe.isNothing :: Maybe a -> Bool
+Data.Maybe.listToMaybe :: [a] -> Maybe a
+Data.Maybe.mapMaybe :: (a -> Maybe b) -> [a] -> [b]
+Data.Maybe.maybeToList :: Maybe a -> [a]
+-- imported via Prelude
+Just :: a -> Maybe a
+data Maybe a = Nothing | Just a
+Nothing :: Maybe a
+maybe :: b -> (a -> b) -> Maybe a -> b
+
+
+ This output shows that, in the context of the current session, in the scope
+ of Prelude, the first group of items from
+ Data.Maybe have not been imported (but are available in
+ fully qualified form in the GHCi session - see ), whereas the second group of items have been
+ imported via Prelude and are therefore available either
+ unqualified, or with a Prelude. qualifier.
+
@@ -1965,6 +2022,17 @@ Prelude> :. cmds.ghci
+
+ :
+ :
+
+
+ Repeat the previous command.
+
+
+
+
+
:history [num]:history
@@ -2082,6 +2150,37 @@ Prelude> :main foo bar
["foo","bar"]
+
+ We can also quote arguments which contains characters like
+ spaces, and they are treated like Haskell strings, or we can
+ just use Haskell list syntax:
+
+
+
+Prelude> :main foo "bar baz"
+["foo","bar baz"]
+Prelude> :main ["foo", "bar baz"]
+["foo","bar baz"]
+
+
+
+ Finally, other functions can be called, either with the
+ -main-is flag or the :run
+ command:
+
+
+
+Prelude> let foo = putStrLn "foo" >> System.Environment.getArgs >>= print
+Prelude> let bar = putStrLn "bar" >> System.Environment.getArgs >>= print
+Prelude> :set -main-is foo
+Prelude> :main foo "bar baz"
+foo
+["foo","bar baz"]
+Prelude> :run bar ["foo", "bar baz"]
+bar
+["foo","bar baz"]
+
+
@@ -2523,18 +2622,34 @@ Prelude> :set -fno-glasgow-exts
When it starts, unless the -ignore-dot-ghci
- flag is given, GHCi reads and executes commands from
- ./.ghci, followed by
- $HOME/.ghci.
-
- The .ghci in your home directory is
- most useful for turning on favourite options (eg. :set
- +s), and defining useful macros. Placing a
- .ghci file in a directory with a Haskell
- project is a useful way to set certain project-wide options so you
- don't have to type them everytime you start GHCi: eg. if your
- project uses GHC extensions and CPP, and has source files in three
- subdirectories A, B and C, you might put the following lines in
+ flag is given, GHCi reads and executes commands from the following
+ files, in this order, if they exist:
+
+
+
+ ./.ghci
+
+
+ appdata/ghc/ghci.conf,
+ where appdata depends on your system,
+ but is usually something like C:/Documents and Settings/user/Application Data
+
+
+ On Unix: $HOME/.ghc/ghci.conf
+
+
+ $HOME/.ghci
+
+
+
+ The ghci.conf file is most useful for
+ turning on favourite options (eg. :set +s), and
+ defining useful macros. Placing a .ghci file
+ in a directory with a Haskell project is a useful way to set
+ certain project-wide options so you don't have to type them
+ everytime you start GHCi: eg. if your project uses GHC extensions
+ and CPP, and has source files in three subdirectories A, B and C,
+ you might put the following lines in
.ghci:
@@ -2548,7 +2663,7 @@ Prelude> :set -fno-glasgow-exts
until the next :load, though.)
Two command-line options control whether the
- .ghci files are read:
+ startup files files are read:
@@ -2557,8 +2672,8 @@ Prelude> :set -fno-glasgow-exts
- Don't read either ./.ghci or
- $HOME/.ghci when starting up.
+ Don't read either ./.ghci or the
+ other startup files when starting up.
@@ -2567,8 +2682,8 @@ Prelude> :set -fno-glasgow-exts
- Read .ghci and
- $HOME/.ghci. This is normally the
+ Read ./.ghci and the other
+ startup files (see above). This is normally the
default, but the option may
be used to override a previous
option.