Manual Reference Pages - regmatch (3)
NAME
regmatch(3f) - [M_regex] return selected substring defined by the MATCHES(2,:) array
CONTENTS
Synopsis
Description
Options
Returns
Example
SYNOPSIS
function regmatch(match,string,matches)character(len=matches(2,match)-matches(1,match)+1) :: regmatch integer, intent(in) :: match, matches(2,*) character(len=*), intent(in) :: string
DESCRIPTION
A convenience function to return a specific substring from the input STRING, defined by the MATCHES() array.
OPTIONS
match the count into the start and end matrix matches(:,MATCH) string the string to find the substrings in matches the start and end matrix generated from calling REGEXEC(3f).
RETURNS
regmatch the selected substring extracted from STRING.
EXAMPLE
Sample program:
program demo_regmatch ! read regular expression from command line and look for it in lines read from stdin. use M_regex, only: regex_type, regcomp, regexec, regmatch, regfree implicit none integer :: command_argument_length character(len=:),allocatable :: command_argument character(len=1024) :: input_line type(regex_type) :: regex logical :: match integer,parameter :: max_subexpressions=10 integer :: matches(2,max_subexpressions) integer :: ios !find length of command argument call get_command_argument(number=1,length=command_argument_length) ! allocate a string long enough to hold the argument allocate(character(len=command_argument_length) :: command_argument) ! get the command argument call get_command_argument(1, command_argument)! compile up regular expression call regcomp(regex,command_argument,’x’)
! read lines and look for match to expression INFINITE: do read(*,’(a)’,iostat=ios)input_line if(ios.ne.0)exit INFINITE ! look for a match in (remaining) string match=regexec(regex,input_line,matches) ! if no match found go for next line if(.not.match)cycle INFINITE ! show line with match write(*,’(a)’) trim(input_line) enddo INFINITE
! free memory used for compiled regular expression call regfree(regex)
end program demo_regmatch
| regmatch (3) | April 06, 2020 |
