f# - Generalizing a new operator over many types -

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i using unquote , did not see approximate comprison. decided write one.

let inline (=~=) x y = abs x-y <  1.e-10

however operator not mapped onto, lists

let test  = [1;2] =~= [1;2]  //---> error

is possible declare operator flow (=) ?

or require define new traits 'structuralequality-ishness"?

is better define new operator with, say, http://code.google.com/p/fsharp-typeclasses/ ?

i don't know unquote, regarding approximate function/operator i'm not sure if there way implement structural comparison.

if want "by hand", using technique (or trick) similar 1 used f# typeclasses project, here example:

type approximate = approximate     static member inline ($) (approximate, x:^n       ) = fun (y:^n) -> float (abs (x-y)) <  1.e-10     static member inline ($) (approximate, x:list< ^n>) =          fun (y:list< ^n>) ->              x.length = y.length && (list.zip x y |> list.forall ( fun (a,b) -> (approximate $ a) b)) // more overloads let inline (=~=) x y = (approximate $ x) y

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