If ^a^b replaces “a” once in the last command, what do I use to replace all occurrences of “a”?

Question

In bash, if I run this command:

echo aaaaaaa

I get aaaaaaa (duh)

But then if I type in

^a^b

I end up with baaaaaa

What would I type to end up with bbbbbbb ?

Answer 1

In bash, I don't think you can combine the ^ shortcut with any modifier. That leaves the long form:

!!:gs/a/b/

In zsh, the G modifier is a special case, you can use it with ^:

^a^b^:G

Answer 2

^search^replacement is syntactic sugar for !:s/search/replacement/, which is explained in this answer. The version that replaces all instances is !:gs/search/replacement/; I think that's the shortest form there is