fix(stringification): reduce clashes,better format

This commit does the following:

1. Renames the `string_m` module and `string` function to
   `fortran_stringify_integer_m` and `fortran_stringify_integer`,
   respectively, to decrease the likelihood of name clashes with
   user code and to clarify the function's limited purpose.
2. Renames the `STRINGIFY` macro to `CPP_STRINGIFY_SOURCE` to more
   clarify the difference from `fortran_stringify_integer`.
3. Changes the `fortran_stringify_integer` string-writing format
   from `*` to `(i0)` for more consistent results across compilers.
   The results are the same for the three tested compilers:
   GCC (`gfortran`), NAG (`nagfor`), and LLVM (`flang-new`).

Author: rouson

include/assert_macros.h

@@ -13,18 +13,18 @@
 
 ! Deal with stringification issues:
 ! https://gcc.gnu.org/legacy-ml/fortran/2009-06/msg00131.html
-#ifndef STRINGIFY
+#ifndef CPP_STRINGIFY_SOURCE
 # if defined(__GFORTRAN__) || defined(_CRAYFTN) || defined(NAGFOR)
-#  define STRINGIFY(x) "x"
+#  define CPP_STRINGIFY_SOURCE(x) "x"
 # else
-#  define STRINGIFY(x) #x
+#  define CPP_STRINGIFY_SOURCE(x) #x
 # endif
 #endif
 
 #if ASSERTIONS
-# define call_assert(assertion) call assert_always(assertion, "call_assert(" // STRINGIFY(assertion) // ") in file " // __FILE__ // ", line " // string(__LINE__))
-# define call_assert_describe(assertion, description) call assert_always(assertion, description // " in file " // __FILE__ // ", line " // string(__LINE__))
-# define call_assert_diagnose(assertion, description, diagnostic_data) call assert_always(assertion, description // " in file " // __FILE__ // ", line " // string(__LINE__), diagnostic_data)
+# define call_assert(assertion) call assert_always(assertion, "call_assert(" // CPP_STRINGIFY_SOURCE(assertion) // ") in file " // __FILE__ // ", line " // fortran_stringify_integer(__LINE__))
+# define call_assert_describe(assertion, description) call assert_always(assertion, description // " in file " // __FILE__ // ", line " // fortran_stringify_integer(__LINE__))
+# define call_assert_diagnose(assertion, description, diagnostic_data) call assert_always(assertion, description // " in file " // __FILE__ // ", line " // fortran_stringify_integer(__LINE__), diagnostic_data)
 #else
 # define call_assert(assertion)
 # define call_assert_describe(assertion, description)

src/assert/string_m.f90 …c/assert/fortran_stringify_integer_m.f90src/assert/string_m.f90 renamed to src/assert/fortran_stringify_integer_m.f90 src/assert/string_m.f90 renamed to src/assert/fortran_stringify_integer_m.f90

@@ -1,16 +1,16 @@
-module string_m
+module fortran_stringify_integer_m
   implicit none
 
 contains  
 
-   pure function string(number) result(number_as_string)
+  pure function fortran_stringify_integer(number) result(number_as_string)
     integer, intent(in) :: number
     integer, parameter :: max_len=128
     character(len=max_len) :: untrimmed_string
     character(len=:), allocatable :: number_as_string
 
-    write(untrimmed_string, *) number
+    write(untrimmed_string, '(i0)') number
     number_as_string = trim(adjustl(untrimmed_string))
   end function
 
-end module string_m
+end module

src/assert_m.f90

@@ -1,7 +1,7 @@
 module assert_m
-  use intrinsic_array_m
-  use assert_subroutine_m
-  use characterizable_m
-  use string_m, only : string
+  use intrinsic_array_m, only : intrinsic_array_t
+  use assert_subroutine_m, only : assert, assert_always
+  use characterizable_m, only : characterizable_t
+  use fortran_stringify_integer_m, only : fortran_stringify_integer
   implicit none
-end module assert_m
+end module