Editorial standards Show Comments
Полузащитник «Зенита» Ерохин заявил о готовности сменить игровую позициюПолузащитник «Зенита» Ерохин заявил о готовности сыграть на позиции нападающего
。关于这个话题，下载安装汽水音乐提供了深入分析
something that i want to claim is that we don’t actually need state machines to be finite at all. in a classical automata world, you would think i am crazy, but we can have an infinite number of states, and it’s fast, practical and also guaranteed to terminate. scrap the “finite” and just call it a “deterministic automaton”. this pulls the rug out from under the feet of a lot of theoretical work in automata theory, and it’s a lot harder to grasp, but it gives us a lot of freedom to do things that are impossible in the classical framework, namely context awareness via lookarounds.
and this is the crux of why we care: extended operators do not make sense with an ordered OR. if | isn’t commutative, then boolean algebra falls apart. A & B is supposed to equal B & A. ~~A is supposed to equal A. these identities rely on | being true union, not “try left first”. so if you want & and ~ to work correctly, you need commutative semantics. it’s not a style choice, it’s a mathematical necessity. and surprisingly also a reason for our amazing benchmark results - leftmost-longest lets you simplify your regexes without changing the matches, which i will elaborate on in another post, but for now just take my word for it that this is a huge deal for performance.