Question

I have this string

blah --arg1 --arg2 --etc doh

sometimes doh ending in slash, sometimes not.

i need to extract doh and assign to a var.

then replace it with /some/path/doh

I wont put here my tries, they are way too ugly.

— updated —

mm, not sure i understand the answers, sorry.

the final string should be like:

blah --arg1 --arg2 --etc /some/path/doh

and doh assigned to a var, say foo

Answer 1

kinda ugly but working

first of all getting rid of eventual trailing slashes:

$ str='blah --arg1 --arg2 --etc doh///'
$ str=$(shopt -s extglob; echo "${str%%+(/)}")
$ echo $str
blah --arg1 --arg2 --etc doh

next extracting doh

$ var=${str##* }
$ echo $var
doh

and lastly removing it from string and adding back prefixed by /some/path

$ echo "${str%"$var"} /some/path/$var"
blah --arg1 --arg2 --etc  /some/path/doh