Store bash string comparison in variable

Question

I want to store the result of a bash string comparison in a variable, with effect equivalent to:

if [[ $a == $b ]]; then
    res=1
else
    res=0
fi

I was hoping to be able to write something terser, like:

res2=$('$a'=='$b') #Not valid bash

Is there a way to achieve what I want, without deferring to an if construct?

Answer 1

I would suggest either:

res=0; [ "$a" == "$b" ] && res=1

or

res=1; [ "$a" == "$b" ] || res=0

Not quite as simple as you were hoping for, but does avoid the if ... else ... fi.