function - Infix operator with missing argument -


is possible haskell have operator (infix function) working missing argument ? (rather - meaning subtraction or negative sign)

for example, have operator : 

data1 <*> data2

is possible make work default value if first argument omitted ?

<*> data2

not really, no. on other hand, define different operation provides default argument, e.g.

withdef data2 = {- default value -} <*> data2

if want use name otherwise operator, can still name partially applied function operator name:

($<*>) data2 = {- default value -} <*> data2

it can used prefix, in ($<*>) data2, or postfix appropriate ghc extensions, in (data2 $<*>). parentheses not optional.


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