[v2-beta7] Possible BoundFunc MinParams bug Topic is solved

[Descolada]

Hello,

Code: Select all

f := TheFunc.Bind(42)
MsgBox(f.MinParams)
f("")

TheFunc(param1, param2) {
    MsgBox("TheFunc: " param1)
}

Expected behaviour would be for f.MinParams == 1, but the result is that f.MinParams == 0. Calling f() throws a "Missing a required parameter" error. Am I missing something here?
I discovered this while trying to pass a BoundFunc into CallbackCreate, but it seems it isn't working without specifying the required param count, which is supplied by func.MinParams...

[swagfag]

yeah, u missed the part where it says

Other properties and methods are inherited from Func, but do not reflect the properties of the target function or method (which is not required to be implemented as a function). The BoundFunc acts as an anonymous variadic function with no other formal parameters, similar to the fat arrow function below:

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Func_Bind(fn, bound_args*) {
    return (args*) => (args.InsertAt(1, bound_args*), fn(args*))
}

u can recover the target function and do some math to figure what its "new MinParams" count should be, and then override BoundFunc's methods to use that procedure instead:

Code: Select all

#Requires AutoHotkey v2.0-beta.4

TheFunc(param1, param2) {
    MsgBox("TheFunc: " param1)
}

f := TheFunc.Bind(42)
pf := ObjPtr(f)
BoundParamsArray := ObjFromPtrAddRef(NumGet(pf, (A_PtrSize = 4) ? 44 : 72, 'Ptr'))
WrappedTheFunc := ObjFromPtrAddRef(NumGet(pf, (A_PtrSize = 4) ? 36 : 56, 'Ptr'))

actuallyBoundParamsCount := 0
Loop BoundParamsArray.Length
	if BoundParamsArray.Has(A_Index) ; handles func.Bind(, , , 42) type scenarios
		++actuallyBoundParamsCount

actualMinParams := WrappedTheFunc.MinParams - actuallyBoundParamsCount

MsgBox actualMinParams

this isnt an exhaustive implementation, u still need to handle BoundFuncs of BoundFuncs, methods, closures and probably other edge cases i havent yet thought of