javascript - js regexp - group priority -

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lets say, there multiple regular expressions

  1. .+
  2. (?:bbb )?ccc

which combined in single expression groups - /^(first) (second)$/

both groups should not "know" each other (meaning - can't change expressions).

/^(.+) ((?:bbb )?ccc)$/.exec('aaa bbb ccc');

the current result:

 ["aaa bbb ccc", "aaa bbb", "ccc"]

the expected result:

 ["aaa bbb ccc", "aaa", "bbb ccc"]

how prioritize groups bbb ends in second one?

make first .+ (which inside capturing group) non-greedy adding reluctant quantifier ? next +

^(.+?) ((?:bbb )?ccc)$

demo

> /^(.+?) ((?:bbb )?ccc)$/.exec('aaa bbb ccc'); [ 'aaa bbb ccc',   'aaa',   'bbb ccc',   index: 0,   input: 'aaa bbb ccc' ]

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