RegExp sub-pattern reuse for different open-close conditions?

Question

Is it possible to reuse a matching RegExp sub-pattern for a variety of opening and closing conditions of the containing pattern?

I have a complex/long RegExp sub-pattern for a certain expression X, which I expect to reside within any of the open-close statements, defined as: ${...}, $(...), $[...], $/.../, etc., which in combination makes the whole pattern (mixing open-close conditions is not accepted, or it would have been trivial).

What I want is to avoid repeating the same long X sub-pattern for each of the open-close conditions (using |) when defining the whole pattern, as it becomes too long and unreadable, even though it is mostly just repeated X sub-pattern.

My question - is this achievable within the RegExp syntax? And if yes, then how?

Environments: Node 0.12 for ES5 and IO.js 2.0 for ES6.

P.S. Strictly speaking, we are talking RegExp optimization here, for better code readability, and, possibly, performance.

Answer 1

You can use an extremely hacky way of matching specific opening and closing braces when used together:

\$(?:(\[)|(\()|({)|(\/)).*?(?:(?=\2)(?=\3)(?=\4)\]|(?=\1)(?=\3)(?=\4)\)|(?=\1)(?=\2)(?=\4)}|(?=\1)(?=\2)(?=\3)\/)
                        ^^^ Inner Match Here

It basically looks for all groups except one specific one to be empty and happens to only work in JavaScript regex. The .*? section pointed out in the above code just needs to be replaced with the regex to be matched inside of the braces to match an arbitrary pattern.

Demo: https://regex101.com/r/aX7rH1/1

// Matches
${...}
$(...)
$[...]
$/.../
// Does Not Match
${...)
${...]
${.../
$(...}
$(...]
$(.../
$[...}
$[...)
$[.../
$/...}
$/...)
$/...]