问题
I know most regular expression engines, including the one in JavaScript have \b to match a word boundary, be it at either the start or end of a word.
But Vim also has two more specific regular expression atoms:
- \< matches only the word boundary at the start of a word
- \> matches only the word boundary at the end of a word
Does JavaScript have an equivalent to these atoms, and if not is there a way to express their more precise semantics some other way?
回答1:
As far as I know there is nothing predefined. But what you can do is, to add a lookahead to the word boundary, to check if it is the start or the end of the word.
\< would be then \b(?=\w). This checks if after the word boundary a word character is following ==> start of the word. See this as example on regexr
\> would be then \b(?!\w). This checks if after the word boundary not a word character is following ==> end of the word
来源：https://stackoverflow.com/questions/13453618/are-there-javascript-equivalents-of-the-vim-regular-expression-start-and-end-of