basic haskell : Converting Type to Int -


if have type, eg insurance number int.

is there anyway can convert insurancenumber int use in comparing function?

intni :: ni -> int intni x = int (x)

if, suspect, ni defined as

type ni = int

then can say

intni :: ni -> int intni x = fromintegral x

or, after eta-conversion:

intni :: ni -> int intni = fromintegral

on other hand, seems that

data ni = ni int

in case right way go pattern matching, so:

intni (ni x) = x

this extract x bit out of ni x , return it.


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