#184 Intrinsic preprocessor string support enhancements

[p1ranha-rob]

As a heavy preprocessor user, I would definitely like to see the addition of the following preprocessor additions.
Note that the syntax is in keeping with the current nasm preprocessor syntax:

%strchr  %%pos 'StringToSearch', 'x'            ; %%pos assigned 0
%strstr  %%pos  'StringToSearch', 'To'          ; %% pos assigned 7

as well as their case-insenstive counterparts:

%strchri  %%pos 'StringToSearch', 'X'
%strstri  %%pos  'StringtoSearch', 'TO'

Also nice to haves would be ctype.h is* functions - eg:

%isalpha %%bool 'X'       ; %%bool assigned 1
%isdigit %%bool 'X'         ; %%bool assigned 0
%isalnum %%bool 'X'
%ispunc %%bool 'X'
%isspace %%bool 'X'

where 'X' can be any preprocessor defined string variable or literal

Oh, and a regex command would be incredible

[nasm64developer]

> As a heavy preprocessor user, I would definitely like to see the addition
> of the following preprocessor additions.
> Note that the syntax is in keeping with the current nasm preprocessor
> syntax:
>
> %strchr  %%pos 'StringToSearch', 'x'            ; %%pos assigned 0
> %strstr  %%pos  'StringToSearch', 'To'          ; %% pos assigned 7
>
> as well as their case-insenstive counterparts:
>
> %strchri  %%pos 'StringToSearch', 'X'
> %strstri  %%pos  'StringtoSearch', 'TO'

I once added %STRPOS to my NASM version -- so yeah, this *is* useful. :-)

Note that there is a difference between C and NASM when it comes to what
that "i" means. In C you will get case-insensitive comparisons. In NASM you
will get a result with a case-insensitive name.

> Also nice to haves would be ctype.h is* functions - eg:
>
> %isalpha %%bool 'X'       ; %%bool assigned 1
> %isdigit %%bool 'X'         ; %%bool assigned 0
> %isalnum %%bool 'X'
> %ispunc %%bool 'X'
> %isspace %%bool 'X'
>
> where 'X' can be any preprocessor defined string variable or literal

You would probably want to match C, i.e. require single character operands.

Also, NASM does have %if[id|num|str|token|empty], %strlen, and %substr. So
most of you you are looking for can already be implemented with macros.

> Oh, and a regex command would be incredible

You'd end up picking one of many regex standards or implementations.

Also, you might as well go for %SYSTEM ... to execute arbitrary things.

Personally I believe that regex support is best left to tools other than NASM.

[H. Peter Anvin]

These and a lot of other things would be nicer to have as preprocessor functions; the existing "define a single-line macro" stuff really is an ugly hack.