How does the regex match operator work?

[itsanonmelody]

Newbie here. I'm currently reading the documentation and came across the regex match operator (=~) on the simple expression language page. This is the first time I've seen such an operator and its functionality is not explained by the documentation. I also couldn't find a GitHub discussion related to this feature. Can someone explain it to me?

[itsanonmelody]

Currently learning BASH and stumbled upon this operator: https://tldp.org/LDP/abs/html/bashver3.html#REGEXMATCHREF

Assuming eww's regex match operator work the same, then a =~ b is equivalent to matches(a, b), where a is a string and b is a regular expression.

Is this correct?

[itsanonmelody]

Took the liberty to go through the source code. The regex match operator works exactly like described above.

https://github.com/elkowar/eww/blob/master/crates/simplexpr/src/eval.rs#L240-L243