javascript multiline regexp replace

"foo\r\nbar".replace(/(foo).+/m, "bar")

Hello. I can not understand开发者_如何学编程 why this code does not replace foo on bar

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I can not understand why this code does not replace foo on bar

Because the dot . explicitly does not match newline characters.

This would work:

"foo\r\nbar".replace(/foo[\s\S]+/m, "bar")

because newline characters count as whitespace (\s).

Note that the parentheses around foo are superfluous, grouping has no benefits here.

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JavaScript does not support a dot-all modifier. A common replacement is:

"foo\r\nbar".replace(/(foo)[\s\S]+/, "bar")

/m makes ^ and $ behave correctly, but has not effect on ..