OpenEuphoria

RE: Declaring a Function Before it is used

• Posted by Matt Lewis <matthewwalkerlewis at yahoo.com> Oct 29, 2003
• 472 views

Derek Parnell wrote:
> 
> From: "Mike Nelson" 

<snip>

> > I would suggest "declare" as a new keyword, used as below:
> > 
> > declare function foo(3) -- the digit is the number of parameters
> > 
> > declare global procedure bar(0)
> > 

IMO this isn't really much cleaner than the routine_id() way.  And it 
still matters where you put the declare.  

<snip>

> So why bother? Either do the 'C' thing ...
> 
>    declare function foo(sequence , integer , integer)
> 
> or don't have a 'declare' but have the interpreter keep a fix-up 
> table during the (single) parse pass.

I like this idea better (the VB-ish, fix-up table).

<snip>

> One really annoying aspect of routine_id() is that it doesn't do 
> forward referencing either. If it did, it would simplify libraries 
> like Win32lib and Diamond. We could then test for the existance of 
> user-written routines - in win32lib's case, I could test for 
> routine names like "onPaint_MyWindow" etc.. so the user of the 
> library didn't have to do a setHandler() at runtime.

This would be easier to implement (in fact, looking at the RDS source, 
Rob has comments that make it clear that it was a conscious decision to 
disallow run-time forward referencing, rather than a consequence of the 
design), although I prefer having explicit event handling connections.  
Of course, you'd have to keep setHandler() to allow for single handlers 
for multiple events and controls.

Matt Lewis