List of the Prelude haskell operators, with precedence level-CodePudding

Where can I find a list of the infix Haskell operators in Prelude and base package in general, along with their precedence level, and whether they're right or left associative? I know this information is available in the documentation, but it's all spread out and mixed with descriptions and examples. I just want the list of these operators, without any descriptions, sorted by their precedence level and associativity. That is it.

CodePudding user response：

I found a way to generate this list automatically. First, write the operators to a file. Call it ops:

import Data.Function
import Data.Functor
import Control.Monad
import Data.Bits
:info $ $! . & :    !! <$ <$> $> >>= >> >=> <* <*> *> == /= < > <= >= && ||   - * / `div` `mod` `divMod` `seq` ** ^ ^^ `elem` `notElem` .&. .|.

Then run the following:

> cat ops | ghci | grep infix | LC_ALL=C sort -s -k 2,2 -k 1,1
infixr 0 $
infixr 0 $!
infixr 0 `seq`
infixl 1 &
infixl 1 >>=
infixl 1 >>
infixr 1 >=>
infixr 2 ||
infixr 3 &&
infix 4 ==
infix 4 /=
infix 4 <
infix 4 >
infix 4 <=
infix 4 >=
infix 4 `elem`
infix 4 `notElem`
infixl 4 <$
infixl 4 <$>
infixl 4 $>
infixl 4 <*
infixl 4 <*>
infixl 4 *>
infixl 5 .|.
infixr 5 :
infixr 5   
infixl 6  
infixl 6 -
infixl 7 *
infixl 7 /
infixl 7 `div`
infixl 7 `mod`
infixl 7 .&.
infixr 8 **
infixr 8 ^
infixr 8 ^^
infixr 9 .
>

Some operators won't appear in the output, because their fixity was unspecified. They have fixity infixl 9, which is the default. Notably, this includes !!.

CodePudding user response：

Page 51 of the Haskell Report has a table summarising the fixity of all Prelude operators.