Use vars or repeat in /regex/.test

Question

How to use variables or repeat through string in regular expressions?

/^(var1)bar(var1)$/.test('foobarfoo') //true

Answer 1

You want something like this:

So if you wanted to replace "foobarbaz" into "bazbarfoo", you'd do this in sed like this (not sure what language you are using):

s/^(foo)(bar)(baz)$/\3\2\1/

You first capture your desired output with brackets () and then you can use the matches with backreferences like \1 \2 \3.

Answer 2

Is that what you want?

console.log(/^([a-z]+)bar\1$/.test('foobarfoo'));