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Re: overloading a function name in a package? How to query all names?

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  • Subject: [mg110833] Re: overloading a function name in a package? How to query all names?
  • From: Vincent <sheeplane at>
  • Date: Thu, 8 Jul 2010 03:14:17 -0400 (EDT)
  • References: <i0urgq$6kp$>

On Jul 6, 11:03 am, "Nasser M. Abbasi" <n... at> wrote:
> Hello;
> I have package where I overloaded the same function name, defined to
> accept different arguments. as follows:
> -------------------
> BeginPackage["foo`"]
> boo1::usage="call me as follows: boo1[a,b]"
> boo1::usage="call me as follows: boo1[a]"
> Begin["`Private`"]
> boo1[a_,b_]:=Module[{},Print["in v1 of boo1"]];
> boo1[a_]:=Module[{},Print["in v2 of boo1"]];
> End[]
> EndPackage[]
> --------------------------------
> Now, I do
> <<foo`
> And I can call either of them OK
> boo1[1,2]
> boo1[1]
> But when I do
> Names["foo`*"]
> It only shows name boo1 once. (I can understand this*)
> And when I do
> ?foo`*
> It only list boo1 once. It seems to show the ::usage of the last one.
> OK. I can understand this.
> But, then, is there a way to show the user than I have more than one
> version of the same function name in the package? Without having to look
> into the package file?
> I'd like to overload the function name, since I need to call it
> differently sometimes, and I do not want to make up new names of the
> same function, as in booV1[], booV2[], etc... since they all do the same
> logical action, but accept different arguments depending on the options
> needed, and so they all just have the same name, and the correct version
> will be called depending on the arguments used.
> Overloading works OK when calling. I am just asking on how to show that
> I have more than one function of the same name in the package, so I know
> how to call each one.
> I looked a the docs, but so far, did not see anything. will keep looking.=
> thanks
> --Nasser

I'm not an expert, but I think you just have your terminology mixed.
You don't actually have two different functions, you have a single
function which acts differently depending on its number of arguments.
It's like for example that List[1,2,3] is the same function as
List[1,2]. So you should state in your usage definition that the
function acts in one way when given one input, and another given two

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