Feature Request: Add @ operator to SUB and FUNCTION arguments

[orlof]

Example:

SUB SomeTimeCriticalRoutine(Value AS BYTE @30) STATIC
  'Some fine code
END SUB

This would allow reuse of ZP addresses in multiple time critical subroutines.

[JJFlash-IT]

This would be quite useful even with normal addresses, so that one would be able to reuse memory among different subs and functions while keeping the speed of STATIC procedures

[orlof]

Even fancier way would be to allow renaming e.g.

DIM zp AS BYTE FAST
SUB SomeTimeCriticalRoutine(Value AS BYTE @zp) STATIC
  'Some fine code
END SUB

...but that might be too far from Basic's traditions?

[JJFlash-IT]

I fear that, most of all, it would allow for too messy code. Since parameter (argument) memory locations are bound to be rewritten with each sub/function call, I guess it would be fine to re-use memory, but I wouldn't mess up global (if not shared!) variables.

[neilsf]

I think there are multiple possible improvements here:

• Allow allocating STATIC SUB/FUNCTION parameters on ZP, e.g. SUB example (param AS BYTE FAST) STATIC - note this won't reuse an existing address but assign a new one
• Allow declaring an entire SUB/FUNCTION as FAST, meaning that everything (parameters, local vars and the return value) is allocated on ZP, e.g. SUB example (param AS BYTE) STATIC FAST
• Allow explicit memory address for SUB/FUNCTION parameters, e.g. SUB example (param AS BYTE @$FF) STATIC - note that the address can be a 16-bit value as well

Note that all the above could work together with STATIC only as dynamic SUBS/FUNCTIONS always pass parameters and the return value using the Stack.

Even fancier way would be to allow renaming e.g.

Or you can simply use global variables to share values:

DIM zp AS BYTE FAST
SUB SomeTimeCriticalRoutine() STATIC
  'You can use zp here as it is global
END SUB
zp = 1 ' Assign value instead of passing parameter value
CALL SomeTimeCriticalRoutine ()

[JJFlash-IT]

Basically, argument/parameter variables would be at the same level of variables declared with DIM, which you can declare as FAST OR at a specific address. That I would like :) Yes, the compiler could give a warning and ignore the FAST or specific-address directives, or stop with an error if the sub/function is not declared STATIC.