Velocity: Regex capturing groups

Question

I was wondering if there's a possibility in velocity to use regex capturing groups? So, as a simple example, we may want to get "Some Name", "13:00" and "14:00" from the following input string: "Some Name: 13:00 - 14:00".
 
There are multiple ways how this can be achieved but one possibility would be to use a simple regex such as "^(.+):\s?(\d{1,2}:\d{1,2})\s?\-\s?(\d{1,2}:\d{1,2})$" and then extract the parts from the three capturing groups.
 
Something like "matches" in Velocity only returns a Boolean which can be used to e.g. compare a input to a pattern.
 
#set( $input = "Some Name: 13:00 - 14:00" )
#set( $regex = "^(.+):\s?(\d{1,2}:\d{1,2})\s?\-\s?(\d{1,2}:\d{1,2})$" )
#if ( $input.matches($regex) )
  ## We have a match
#end

In JavaScript land you could e.g. do something simple such as
 
const [_, name, timeFrom, timeTo] = "Some Name: 13:00 - 14:00".match(/^(.+):\s?(\d{1,2}:\d{1,2})\s?\-\s?(\d{1,2}:\d{1,2})$/i) || [];
 
Is there something similar in Velocity? Given the example above, we could "split" by multiple delimiters or use multiple "replace" runs to get the parts but that obviously has its limitations and feels somewhat hacky.
Maybe @sanfordwhiteman has an idea? Thanks in advance.

SanfordWhiteman · Accepted Answer

It's not so much capturing groups you're lacking (which are supported) it's an iterable set of match results.

In Marketo's Velocity, you can't create a Matcher object (other Velocity installs do support this).

The closest way to simulate would be replaceAll and put a known-unused delimiter - like the ASCII record delimiter in the below example - then split on the delimiter.

#set( $input = "Some Name: 13:00 - 14:00" )
#set( $regex = "^(.+):\s?(\d{1,2}:\d{1,2})\s?\-\s?(\d{1,2}:\d{1,2})$" )
#set( $output = $input.replaceAll( $regex, "$1\u001e$2\u001e$3" ).split("\u001e") )
#foreach( $part in $output )
${part}
#end

Figure I'll do a blog post on this one of these days.

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