regex sub match math

Test 300
Test 301
Test 302

I can use regex find to loop through these:

Test (3[0-9]*)

When I try replace with math it concatenates instead of evaluates?

Test $1-100

So, it becomes:

Test 300-100

Is it possible to evaluate instead of concatenate, so it becomes:

Test 200

It works in vim regex:

%s@Test (3[0-9]*)@\='Test '.(submatch(1)-100)@

Thanks.

[NonsenseInc]

why not integrate a eval operator like ${some javascript}. Let me give an example:

input 99 bottles of beer on the wall, 99 bottles of beer. Take one down and pass it around, 98 bottles of beer on the wall. search (\d+) replace with ${$1 - 1} result 98 bottles of beer on the wall, 98 bottles of beer. Take one down and pass it around, 97 bottles of beer on the wall. search (\w+) replace with ${$1.split('').reverse().join('')} result 89 selttob fo reeb no eht llaw, 89 selttob fo reeb. Ekat eno nwod dna ssap ti dnuora, 79 selttob fo reeb no eht llaw.

I think that would be very useful.

[renehamburger]

There has been a response to @rakkarage’s StackOverflow question by now: this can be achieved by the Super Replace VS Code extension: