Parse a variable as if it were parameters?

Question

Is there a way in Bash (without calling a 2nd script) to parse variables as if they were command line arguments? I'd like to be able to group them by quotes and such.

Example:

this="'hi there' name here"

for argument in $this; do
    echo "$argument"
done

which should print (but obviously doesn't)

hi there
name
here

Answer 1

Don't store the arguments in a string. Arrays were invented for this purpose:

this=('hi there' name here)

for argument in "${this[@]}"; do
    echo "$argument"
done

It is highly recommended that you use this approach if you have control over this. If you don't, that is even more reason not to use eval, since unintended commands can be embedded in the value of this. For example:

$ this="'hi there'); echo gotcha; foo=("
$ eval args=($this)
gotcha

Less nefarious is something as simple as this="'hi there' *". eval will expand the * as a pattern, matching every file in the current directory.

Answer 2

I worked out a half-answer myself. Consider the following code:

this="'hi there' name here"

eval args=($this)

for arg in "${args[@]}"; do
    echo "$arg"
done

which prints the desired output of

hi there
name
here