Re: Declare variable type within function

foo(x) == list x

works for you?

Themos Tsikas


On Monday 17 March 2008, Angelos Mantzaflaris wrote:
> Hello,
>
> Here is a newbie question: I am writing some axiom scripts for which I
> don't want to declare I/O types. But, I need to declare, for example, an
> empty list of typeOf(input). I have tried the following:
>
> foo(x)==
> 	L:=[]
> 	L:= append(L,x)
> 	return L
>
> Axiom will complain:
> The type of the local variable L has changed in the computation.
> We will attempt to interpret the code. I also try:
>
> foo(x)==
> 	L:=[]::typeOf(x)
> 	L:= append(L,x)
> 	return L
>
> Axiom will complain again:
> Cannot compile conversion for types involving local variables.
> In particular, could not compile the expression involving :: typeOf
> AXIOM will attempt to step through and interpret the code.
>
> But I can play tricks like this:
>
> foo(x)==
> 	L:=[x.1-x.1]
> 	L:= append(L,x)
> 	return L
>
> And Axiom will compile the function without errors:
> Compiling function foo with type List PositiveInteger List Integer
>
>
> So my question is, how can I do this in a straightforward way (without
> playing tricks)?
>
> Thank you in advance,
> Angelos
>
>
>
>
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