using type conversion syntax to choose the desired version of an overloaded function

ambiguous_fn_ptr.nim

proc foo(x:int) = echo "int ", x
proc foo(x:string) = echo "string ", x

var p1:pointer = (proc(x:int){.nimcall.})(foo)     # p1 gets the int version of foo
var p2:pointer = (proc(x:string){.nimcall.})(foo)  # p2 gets the string version of foo

var f1 = cast[proc(x:int){.nimcall.}](p1)
var f2 = cast[proc(x:string){.nimcall.}](p2)

f1(100)
f2("boo")