Regex with possible empty matches and multi-line match

Question

I\'ve been trying to \"parse\" some data using a regex, and I feel as if I\'m close, but I just can\'t seem to bring it all home.
The data that needs parsing gener

Answer 1

The following regex should work, but I'm not so sure anymore if it is the right tool for this:

preg_match_all(
    '%^            # Start of line
    ([^:]*)        # Match anything until a colon, capture in group 1
    :\s*           # Match a colon plus optional whitespace
    (              # Match and capture in group 2:
     (?:           # Start of non-capturing group (used for alternation)
      .*$          #  Either match the rest of the line
      (?=          #  only if one of the following follows here:
       \Z          #  The end of the string
      |            #  or
       \r?\n       #  a newline
       [^:\n\\\\]* #  followed by anything except colon, backslash or newline
       :           #  then a colon
      )            #  End of lookahead
     |             # or match
      (?:          #  Start of non-capturing group (used for alternation/repetition)
       [^:\\\\]    #  Either match a character except colon or backslash
      |            #  or
       \\\\.       #  match any escaped character
      )*           #  Repeat as needed (end of inner non-capturing group)
     )             # End of outer non-capturing group
    )              # End of capturing group 2
    $              # Match the end of the line%mx', 
    $subject, $result, PREG_PATTERN_ORDER);

See it live on regex101.