On Wed, Sep 21, 2016 at 11:15:45PM -0400, mobatu...@yahoo.ca wrote:
> In Summary:
> declare -a "$string" # results in execution of $string
> declare -a a=($string) # does not result in execution of $string
This is why you don't use the first form. It's the same with eval --
if you don't have full control over the statement being eval'ed, then
you risk undesired code execution.
Your second form also has some issues. The contents of $string will
undergo word splitting and then pathname expansion (globbing). This could
cause unexpected results if any of the words expands to a glob pattern
which matches actual files. If you want to split a string into an array,
this is safer as long as the string does not contain any newlines:
read -ra a <<< "$string"
If the string contains newlines, then:
read -rd '' -a a <<< "$string"
Of course, this read command will always exit with status "1" because
it never finds a NUL byte. That's only a problem if you use set -e,
which of course no sane person should be doing....