How to use regular expressions (\b, \w) in Freemarker?

freemarker, regex

Solution

You need to double the backslashes:

${str?replace("\\d+", "", "r")};

This is because string escaping rules are applied before regex escaping rules. So the string `"\\d"` is translated to the regex `\d` which then matches a digit.

If your string is `"\d"`, the string processor translates it to a literal `d` (because `\d` is not a recognized string escape sequence, so it's ignored).

Problem

``` ${str?replace("\d+", "", "r")}; ``` I wanted to use `\d` to remove numbers, but it didn't work!!! But `${str?replace("[0-9]", "", "r")};` works!!! So, I wanna know how to use regex like `\d`, `\b`, `\w`, etc?

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