Try it online! Try it online! - true/false
Try it online! Try it online! - return value in 1円
Try it online! - true/false
Try it online! - return value in 1円
Try it online! - true/false
Try it online! - return value in 1円
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But because of the difficulty and length of this algorithm, I used molecular lookaheads (of the form (?*...)) to implement it. That is a feature not in ECMAScript or any other mainstream regex engine, but one that I had implemented in my engine. Without any captures inside a molecular lookahead, it's functionally equivalent to an atomic lookahead, but with captures it can be very powerful. The engine will backtrack into the lookahead, and this can be used to conjecture a value which cycles through all possibilities (for later testing) without consuming characters of the input. Using them can make for a much cleaner implementation. (Variable-length lookbehind is for most uses at the very least equal in power to molecular lookahead, but the latter tends to make for more straightforward and elegant implementations. Molecular lookahead may also be able to do things in loops that aren't possible with variable-length lookebehind.)
But because of the difficulty and length of this algorithm, I used molecular lookaheads (of the form (?*...)) to implement it. That is a feature not in ECMAScript or any other mainstream regex engine, but one that I had implemented in my engine. Without any captures inside a molecular lookahead, it's functionally equivalent to an atomic lookahead, but with captures it can be very powerful. The engine will backtrack into the lookahead, and this can be used to conjecture a value which cycles through all possibilities (for later testing) without consuming characters of the input. Using them can make for a much cleaner implementation. (Variable-length lookbehind is at the very least equal in power to molecular lookahead, but the latter tends to make for more straightforward and elegant implementations.)
But because of the difficulty and length of this algorithm, I used molecular lookaheads (of the form (?*...)) to implement it. That is a feature not in ECMAScript or any other mainstream regex engine, but one that I had implemented in my engine. Without any captures inside a molecular lookahead, it's functionally equivalent to an atomic lookahead, but with captures it can be very powerful. The engine will backtrack into the lookahead, and this can be used to conjecture a value which cycles through all possibilities (for later testing) without consuming characters of the input. Using them can make for a much cleaner implementation. (Variable-length lookbehind is for most uses at least equal in power to molecular lookahead, but the latter tends to make for more straightforward and elegant implementations. Molecular lookahead may also be able to do things in loops that aren't possible with variable-length lookebehind.)
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55
- 12.9k
- 2
- 71
- 55