Haskell - Declaring the type of multiple functions -

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i find myself writing multiple functions same type. let's call type functype. might write this:

funca :: functype funcb :: functype funcc :: functype funcd :: functype  -- implementations

this feels lot of unnecessary typing (typing in tapping on keyboard, not declaring types of functions). there maybe way more concisely? want along lines of:

(funca, funcb, funcc, funcd) :: functype  -- implementations

i tried google came empty. if isn't feature of language, why not? missing something? doing wrong if find myself needing this?

do tried without parentheses.

funca, funcb, funcc, funcd :: functype

in haskell 2010 report, can see in chapter 4 (declarations , bindings) type signature (gendecl) looks this:

vars :: [context =>] type

and vars this:

var-1 , … , var-n

which form you're looking for.

sidenote: haddock apply documentation if finds around type signature to every symbol in (vars) list.


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