Sed substitute recursively

Question

echo ddayaynightday | sed \'s/day//g\'

It ends up daynight

Is there anyway to make it substitute until no more match ?

Answer 1

Ok, here they're: while and strlen in bash. Using them one may implement my idea:

Repeat until its length will stop changing.

There's neither way to set flag nor way to write such regex, to "substitute until no more match".