Re: Fortran indentation

[Ken Mankoff <km@kenmankoff.com>]

On 2024-08-27 at 05:17 -07, Eli Zaretskii <eliz@gnu.org> wrote...
>> From: Ken Mankoff <km@kenmankoff.com>
>> 
>> do_foo = some_function()
>>   if (do_foo) then
>> 
>> The if statement should not be indented, because do_foo is not the
>> start of a do loop. I can fix this behavior if I change line 1634 of
>> fortrtan.el from
>> 
>> ((looking-at "do\\b")
>> 
>> to
>> 
>> ((looking-at "do\\ \\b")
>> 
>
> 	DO42000I=1,42
>
> AFAIR is a valid Fortran do-loop starter.

You're right, that is valid. The 'looking-at' regex can be improved to handle this case - match "DO42I=1,42" but not "do_foo = f()".

My first attempt is to expect a space or numbers after "DO": "do[\\ |0-9]+". This still matches a vector assignment of: DO42 = [1,2]

More comprehensive - search for only certain characters on the RHS. do[\\ |0-9]+.*=[\\ a-z0-9_]*,[\\ a-z0-9_]*

The last regex appears to work in regexp-builder with these few tests:

      do42I=1,42 ! match
      do_foo = bar()
      do i = 1,42 ! match
      do i = 1,n ! match
      do i_var = a_var,b_var ! match
      do42i_var = a_var,b_var ! match
      DO42 = [1,2]

Would this change be acceptable?

   -k.