[BUG?]Are numbers valid symbols?

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LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 24 Apr 2011, 00:09

Check this out:

Code:

; OK
1 equ 'one', 13, 10
display 1

; OK
macro 2{
  display 'two', 13, 10
}
2

; INVALID NAME
;macro '3'{
;  display 'three', 13, 10
;}
;'3'

;'4' equ 'four', 13, 10 ; ILLEGAL INSTRUCTION
display '4', 13, 10

5.0 equ 'five', 13, 10
display 5.0

macro 6.0{
  display 'six', 13, 10
}
6.0

This was discovered by ouadji when he tested numerical names on PROC arguments.

24 Apr 2011, 00:09

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20451
Location: In your JS exploiting you and your system

revolution 24 Apr 2011, 01:12

Preprocessor is not sensitive to symbol contents. They are all just strings of characters to be processed as usual.

24 Apr 2011, 01:12

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 24 Apr 2011, 15:28

I think it should, specially because of this:

Code:

1 equ 3
alpha equ 3

rept 1{display 'one, '}

display 13, 10
rept alpha{display 'alpha, '}

display 13, 10
rept alpha+1{display 'alpha+1, '}

Also, are numbers really symbols or just tokens that the preprocessor is unconditionally considering them as symbols but making an exception for REPT?

24 Apr 2011, 15:28

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20451
Location: In your JS exploiting you and your system

revolution 25 Apr 2011, 01:51

rept has special processing to evaluate values so it won't see the 'equ' substitutions for plain numbers.

Code:

display 13, 10
match x,1 {rept x{display 'one, '\}}

25 Apr 2011, 01:51

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8359
Location: Kraków, Poland

Tomasz Grysztar 26 Apr 2011, 18:15

Right, this was not an issue before the new REPT functionality was introduced, however now it is worth a reconsideration. Would disallowing a digit-starting names for symbolic variables cause any problems. I do not think anyone would use this feature for any serious purpose, but I may be wrong.

26 Apr 2011, 18:15

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