Suggestion/request

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Joshua

Joined: 12 Jul 2003
Posts: 56
Location: Belgium

Joshua 01 Aug 2004, 10:25

Priv,

Instead of returning 'error: undefined symbol' on a line like the following, perhaps it is possible to initialise it to blank? (perhaps same for equ and fix)

Ex:

Code:

A = A + 1   -> Error       -> A =  + 1    -> A = 1

But this stays the same:

Code:

A = 5       -> A = 5
A = A + 1   -> A = 5 + 1   -> A = 6

And:

Code:

B = A + 1   -> Error

I know that this can in most cases be emulated with:

Code:

local here
if ~defined A | defined here
    A = 1
    here = 0
else
    A = A + 1
end if

But when using this as a counter it may return incorrect results as explained in this post:
http://board.flatassembler.net/topic.php?p=4322&highlight=#4322

01 Aug 2004, 10:25

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
Location: Kraków, Poland

Tomasz Grysztar 01 Aug 2004, 10:58

The old "defined" behavior was good for this, but the with the new one (since 1.50) it's not possible. Maybe I should re-implement the old "defined" with some new name?

01 Aug 2004, 10:58

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
Location: Kraków, Poland

Tomasz Grysztar 01 Aug 2004, 11:33

I've got a better idea: let the "defined" work the old way specifially with the redefined constants - this will make it even more logical, as those constants cannot be forward-referenced, too, so checking only for backward definition is indeed more suitable for them.

I'm currently testing whether it doesn't cause any problems, it solves your trouble with the code like:

Code:

if ~ defined a
 a = 0
end if
a = a + 1

01 Aug 2004, 11:33

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
Location: Kraków, Poland

Tomasz Grysztar 01 Aug 2004, 11:46

It seems that it works good. The 1.54 release has been updated to include this change. The new behavior of "defined" can be described simply as: it checks whether the symbol has been defined and is accessible from the current position.

01 Aug 2004, 11:46

Joshua

Joined: 12 Jul 2003
Posts: 56
Location: Belgium

Joshua 01 Aug 2004, 23:52

Perfect!

01 Aug 2004, 23:52

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