A work-in-progress collection of Fortran 2018 ISO_C_BINDING interfaces to Perl-compatible Regular Expressions 2 (PCRE2). The library is also available on MacPorts.
You will need libpcre2 with development headers. On FreeBSD, run:
# pkg install devel/pcre2 On Debian Linux, install:
# apt-get install libpcre2-8-0 libpcre2-dev Clone the repository and execute the provided Makefile to create the static library libfortran-pcre2.a containing the interfaces:
$ git clone https://github.com/interkosmos/fortran-pcre2 $ cd fortran-pcre2/ $ make Install the library and the modules files system-wide to /opt:
$ make install PREFIX=/opt Instead of make, you may want to build the library using the Fortran Package Manager:
$ fpm build --profile release Link your Fortran programs against libfortran-pcre2.a and -lpcre2-8.
The following program just compiles and executes a basic regular expression.
! example.f90 program main use :: pcre2 implicit none (type, external) integer, parameter :: OVECSIZE = 30 ! Must be multiple of 3. character(len=128) :: buffer character(len=:), allocatable :: pattern, subject integer :: err_code, rc integer(kind=pcre2_size) :: err_offset type(c_ptr) :: match_data, re pattern = '^([A-Z][a-z]+)$' subject = 'Fortran' ! Compile regular expression. re = pcre2_compile(pattern = pattern, & length = len(pattern, kind=pcre2_size), & options = 0, & errorcode = err_code, & erroroffset = err_offset, & ccontext = c_null_ptr) if (.not. c_associated(re)) then buffer = ' ' rc = pcre2_get_error_message(err_code, buffer, len(buffer, kind=pcre2_size)) print '("Error ", i0, ": ", a)', err_code, trim(buffer) stop end if ! Execute regular expression. match_data = pcre2_match_data_create(OVECSIZE, c_null_ptr) rc = pcre2_match(code = re, & subject = subject, & length = len(subject, kind=pcre2_size), & startoffset = int(0, kind=pcre2_size), & options = 0, & match_data = match_data, & mcontext = c_null_ptr) if (rc == 0) then print '("OVECSIZE too small")' else if (rc < 0) then select case (rc) case (PCRE2_ERROR_NOMATCH) print '("No match")' case default print '("Matching error ", i0)', rc end select else if (rc > 0) then print '("Match!")' end if call pcre2_match_data_free(match_data) call pcre2_code_free(re) end program mainIf the library has been installed to /opt, then compile, link, and run the program with:
$ gfortran -I/opt/include/libfortran-pcre2 -o example example.f90 /opt/lib/libfortran-pcre2.a -lpcre2-8 $ ./example You can add fortran-pcre2 as an FPM dependency:
[dependencies] fortran-pcre2 = { git = "https://github.com/interkosmos/fortran-pcre2.git" }It is not necessary to null-terminate character strings given to the procedures of fortran-pcre2. In contrast to the C API of PCRE2, you must not free substrings with pcre2_substring_free(), as this will be done by the wrapper functions.
| C API | Fortran interface |
|---|---|
pcre2_code_free_8 | pcre2_code_free |
pcre2_compile_8 | pcre2_compile |
pcre2_compile_context_free_8 | pcre2_compile_context_free |
pcre2_get_error_message_8 | pcre2_get_error_message |
pcre2_get_ovector_count_8 | pcre2_get_ovector_count |
pcre2_get_ovector_pointer_8 | pcre2_get_ovector_pointer |
pcre2_match_8 | pcre2_match |
pcre2_match_data_create_8 | pcre2_match_data_create |
pcre2_match_data_free_8 | pcre2_match_data_free |
pcre2_substring_copy_byname_8 | pcre2_substring_copy_byname |
pcre2_substring_copy_bynumber_8 | pcre2_substring_copy_bynumber |
pcre2_substring_free_8 | pcre2_substring_free |
pcre2_substring_get_byname_8 | pcre2_substring_get_byname |
pcre2_substring_get_bynumber_8 | pcre2_substring_get_bynumber |
pcre2_substring_number_from_name_8 | pcre2_substring_number_from_name |
ISC