In other words:

    m/ ^(\S+)    # Grab all non white space at the start into $1
         \s+         # Skip any white space
         ([^:]+)   # Now grab everything that isn't a colon in $2
         :            # End the grab for $2 at the colon 
         \s+        # Skip any white space
        (            # Going to capture into $3
        (?:         # Start non-capturing parens
        (?!         # Start negative lookahead
        \s*         # Look for some white space
        \(rev      # Followed by (rev
        )            # Close negative lookahead
       .)            # Close non-capturing parens
       +)           # So if whitespace followed by (rev, grab it $3
       \s*          # Up until some white space
      (.*)          # Grab everything else after the white space into 
+$4
            /x;
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I really just wanted to demonstrate to the OP how to powerfully use the /x modifier