check if handler exist before using it

Thierry 00bioarchimed at
Fri Nov 9 14:00:53 EST 2007

Hi Jim and Richard,

Well, is it Christmas soon ?
so many interesting answers :)

Ok, but, how does one make the difference between
an unknown "dothisFunction" and any kind of error
in the existing "dothisFunction" ?

Again, those functions can be written by anyone, protected or not...
that's why I talk of a generic solution, but maybe it's not
the good term  - you know, these french guys, when they try
to speak English :-)

And last but not least, the checking comes from inside an external....

So, i've done a quick test, with :
     get xxx()
catch errStr
    answer errStr
end try

and I get:


and didn't find in the Doc how to deal with these Errors numbers ?


> You could use
> on try
>   doThisFunction()
> catch errString
>   --function not available, take action
> end try
> Jim Ault

>> As there is the rev function:
>>            exists( an object ) or  there is .... ,
>> is there something like
>>             exists( <whateverFunction> )  in <anyObject>

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