Is it possible to add if-then-else syntax?
pik33
Posts: 2,374
We have now 2 forms of if available:
if a then b
or
if a then b else c endif
A simplified form
if a then b else c
can be also useful to make the code shorter and easier to read and write when what has to be done for if and else is a simple task - of course if possible and not too complex to implement.
An example of proposed syntax:
if header=1 then bpm=100 else bpm=200
Comments
I tried doing the simplified if/then/else in an earlier compiler version and it did not work at all, so I gave up. I'll take another look at it. You're right, it would be a useful addition, but it's very tricky to specify the syntax in YACC because of all of the if/then forms that exist already .
bpm = 200: if header = 1 then bpm = 100
Is this kosher? Not able to test, atm.
Craig
Edit: Just checked the manual and all indications are "yes" and even "then" can be omitted.
I recompiled a new flexprop and It seems the new syntax is already implemented.
This:
bpm = 200: if header = 1 then bpm = 100
is a good old 8-bit Basic trick and it of course works, but if the variable is used by another cog and changes something there, the result can be something not expected. For the audio it can introduce clicks, for the robot the effects can be more unpleasant (tested...)
Ah, I always use a temporary variable in those cases and only assign the outcome of any decision
Craig
>
Yes, although one has to be careful not to nest the if/then/else on one line: more than one else on a line may not work as expected.
I've also implemented the FreeBasic KILL command to delete files and directories.
The full multi-line syntax is much better for complex if-elseif-else things. The simple if-then-else is for things that are simple. Nested one line ifs may be not readable at all
I will use "kill" in the player - now I have to remove the card from P2 and use a PC to delete files that are broken or contain the music I don't like. After that, pressing del + confirming will delete the file without removing the card.