Peter Thanks for that explanation!
On Wed, 28 Nov 2018 20:27:40 +0100, Peter Bozek wrote: > On Wed, Nov 28, 2018 at 7:30 PM Chip Scheide via 4D_Tech < > 4d_tech@lists.4d.com> wrote: > >> Thanks Kirk, >> >> According to Wiki : >> . - matches any single character >> ( ) - defines a marked subexpression >> * - matches the preceding element zero or more times >> so... as I read the definitions... >> "(.*:)" >> >> match any character(s), before a ":" >> a file path (on a Mac) is <folder> : <folder> : <folder> ... : <file> >> >> Match Regex says: >> "...If you pass arrays, the command returns the position and length of >> the occurrence in the element zero of the arrays and the positions and >> lengths of the groups captured by the regular expression in the >> following elements." >> >> so I would expect(ed) >> Match regex($folderPathMotif;$File_Path;1;$path_pos;$path_len) >> >> to populate the arrays with each occurrence of ":", as your supplied >> code appears to do, >> OR >> if the Match Regex does not find/report all occurrences of ":" to >> report the FIRST instance of a ":", not the last. >> > > Regex behaves like that because, by default, its matching is greedy, what > means it tries to match the pattern to as many characters as possible. In > your case, it tries to find longest run that match pattern .*; - and the > run consist of all characters up to last :. > > If you want the match stop on first occurrence of : you need to make > operator * ungreedy by attaching ? to it. If you try pattern (.*?:) it > should return substring up to first :. While pattern .*: says "find the > longest run of characters ending with :" pattern .*?: means "find the > shortest run of characters ending with : > > Size of array is number of matching groups, in your case 1. This is how it > works, IMHO. If the whole pattern repeats itself several times, you need to > run Match regex in loop. > > HTH, > > -- > > Peter Bozek --------------- Gas is for washing parts Alcohol is for drinkin' Nitromethane is for racing ********************************************************************** 4D Internet Users Group (4D iNUG) Archive: http://lists.4d.com/archives.html Options: https://lists.4d.com/mailman/options/4d_tech Unsub: mailto:4d_tech-unsubscr...@lists.4d.com **********************************************************************
