Difference between revisions of "Cookbook/Compilers and interpreters"

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(General: use a less intimidating example)
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| :i
| :i
Prelude> :i Monad
Prelude> :i True
class Monad m where
data Bool = ... | True -- Defined in GHC.Bool
(>>=) :: m a -> (a -> m b) -> m b
(>>) :: m a -> m b -> m b
return :: a -> m a
fail :: String -> m a
-- Defined in GHC.Base
instance Monad Maybe -- Defined in Data.Maybe
instance Monad IO -- Defined in GHC.IOBase
instance Monad ((->) r) -- Defined in Control.Monad.Instances
instance Monad [] -- Defined in GHC.Base

Latest revision as of 08:33, 25 January 2010


Problem Solution Examples
compiling and linking an executable --make
ghc --make Main.hs               --> Main
compiling without linking -c
ghc -c Foo.hs                    --> Foo.hi, Foo.o
generating Assembler code -S
ghc -S Foo.hs                    --> Foo.hi, Foo.s
generating C code -C
ghc -C Foo.hs                    --> Foo.hc, Foo.hi
linking files into an executable -o
ghc -o test Foo.o Bar.o Baz.p    --> test



Problem Solution Examples
checking a definition  :i
Prelude> :i True
data Bool = ... | True  -- Defined in GHC.Bool
checking a type  :t
Prelude> :t "Hello"
"Hello" :: [Char]

Prelude> :t length
length :: [a] -> Int
loading a file  :l
Prelude> :l Foo.hs
[1 of 1] Compiling Foo              ( Foo.hs, interpreted )
Ok, modules loaded: Foo.
reloading all loaded files  :r
Prelude> :r


Problem Solution Examples
setting a break point  :break
Prelude> :break 2    -- sets a break point in line 2