Re: Proper way to return a string


Ron Shepard wrote:
In article <2006122715420316807-gsande@worldnetattnet>,
Gordon Sande <g.sande@xxxxxxxxxxxxxxxx> wrote:

Probably because for a character function you need to declare a
fixed size but it can vary if you use a subroutine.

Assuming that you use Fortran character variables for "strings". ;-)

Perhaps I misunderstand, but I think you have the same flexibility
with functions and subroutines. Since f77, both allow the result to
be declared as assumed length (i.e. (*), or in f90, (len=*)).

I don't think a function have a character(len=*) RESULT . For example,
for the following code

module string_func_mod
implicit none
contains
subroutine str_sub(aa,bb)
character (len=*), intent(in) :: aa
character (len=*), intent(out) :: bb
bb = aa
end subroutine str_sub
!
function str_func(aa) result(bb)
character (len=*), intent(in) :: aa
character (len=*) :: bb
bb = aa
end function str_func
end module string_func_mod

g95 says

In file string_func.f90:10

function str_func(aa) result(bb)
1
Error: Internal function 'str_func' at (1) cannot be an assumed-length
CHARACTER

For a subroutine argument, the LEN of the character argument is the
same on output as on input, but for a function, the compiler would not
"know" what the LEN of a character (len=*) RESULT is.

.

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