How to iterate through string one word at a time in zsh

bash while-loop zsh expansion

Rob Bednark · Apr 18, 2014 · Viewed 43.1k times · Source

How do I modify the following code so that when run in zsh it expands $things and iterates through them one at a time?

things="one two"

for one_thing in $things; do
    echo $one_thing
done

I want the output to be:

one 
two

But as written above, it outputs:

one two

(I'm looking for the behavior that you get when running the above code in bash)

Answer

In order to see the behavior compatible with Bourne shell, you'd need to set the option SH_WORD_SPLIT:

setopt shwordsplit      # this can be unset by saying: unsetopt shwordsplit
things="one two"

for one_thing in $things; do
    echo $one_thing
done

would produce:

one
two

However, it's recommended to use an array for producing word splitting, e.g.,

things=(one two)

for one_thing in $things; do
    echo $one_thing
done

You may also want to refer to: