Quick "why is it" question

[+atari2600land]

Why is this allowed:

if d=3 && pfread(a, b) then c=0

and this isn't?

if pfread(a, b) && d=3 then c=0

I've often wondered that. Anyway, these variables are just examples and don't really connect to anything i'm working on.

[SeaGtGruff]

Why is this allowed:

if d=3 && pfread(a, b) then c=0

and this isn't?

if pfread(a, b) && d=3 then c=0

It isn't a question of being "allowed" or not. It seems there's a bug in the compiler that prevents the second version from compiling correctly.

 

Here's the compilation and assembly of the first version:

 

.L01    	;  if d = 3  &&  pfread ( a , b )  then c = 0
       	LDA d
       	CMP #3
       	BNE .skipL01
.condpart0
       	LDA a
       	LDY b
       	jsr pfread
       	BNE .skip0then
.condpart1
       	LDA #0
       	STA c
.skip0then
.skipL01

Here's the second version:

 

.L01    	;  if pfread ( a , b )   &&  d = 3 then c = 0
       	LDA a
       	LDY b
       	jsr pfread
       	BNE .skipL01
.condpart0
       	; complex statement detected
       	LDA #3
       	PHA
       	LDA then
       	PHA
       	LDA c
       	PHA
       	LDA =
       	PHA
       	LDA #0
       	STA d
.skipL01

The pfread compiles correctly either way, but for some reason the compiler thinks there's a complex statement after the &&, so it compiles that part incorrectly.

 

Michael