Nothing tastes quite so bitter
As a slice of humble pie
But vengeance will be sweet
As you take an eye for eye
No I'm a Brit who lives in KL
To instruct that such a transgression is actually the least desirable choice, and/or to make such a transgression impossible to perpetrate again. These are reasons to take action. Not to balance some imaginary scale..
Teach them that hurting you will cause them pain one thousand times worse than they caused you, so they will not want to do it again... OR Make it impossible for them to hurt you or your loved one again. (lethal injection or encased in concrete works for this.) It's not about getting even, it's about fixing a problem so it does not happen again.
Some countries do... Their was a seriel killer in Pakistan that was convicted of murder but he had to die the same way as his victims. Each time one parent strangled him (his method of killing) to passing out. They would revive him and let the next parents have a go. It got a bit sickening after awhile...