"Regular expressions" are a mathematically defined concept, invented by Stephen Kleene in 1956. In their most minimalistic (and original) version, these expressions define languages using just literal ...

プログラマーなら一度はこう思ったことがあるはず。「え、なんで ^.*?(foo|bar)+$ で文字列を判定できるの？」「なんで1行で1000文字超えるの？」――そう、それが正規表現、通称「Regex」。 文字列マッチングという一見地味な分野で、なぜここまで厨二病的な ...

This is how to convert regex (REGular EXpression) to DFA by creating and using syntax tree in Java language. This project is a part of a bigger project we'd done for Compiler Course to create a simple ...

I was involved in a recent discussion on the "best" way to remove a given parameter from a URL string. The conversation began with using string primitives to split and join the parameter, a method ...