Re: bash compgen -W compatibility patch

[Peter Stephenson <Peter.Stephenson@xxxxxxx>]

On Tue, 3 May 2011 08:25:50 -0400
Rocky Bernstein <rocky@xxxxxxx> wrote:
> For example simplicity, to match the beginning of a word, I used
>     [[ $try =~ "^$find" ]]
> matching using == and substrings might be faster, not that I think
> speed is all that important here. Ditt ofo inlining a newly added
> _compgen_opt_words function; but I think that makes things uglier and
> harder to test.
>
>...
>
> +_compgen_opt_words() {
> +    typeset -a words
> +    eval "words=( $1 )"
> +    local find
> +    find=$2
> +    local try
> +    find=${@[-1]}
> +    for try in ${words[@]} ; do 
> +	if [[ $try =~ "^$find" ]] ; then 
> +	    results+=( $try )
> +	fi
> +    done
> +    results=( "${(k)results[@]}" )
> +}

Thanks.  It's actually possible to abbreviate this quite a lot, in ways
which are used widely in the completion code.  Also, the eval looks a
bit hairy because $1 can contain anything, and I think it's good enough
to ensure that $1 is split into words and any pattern characters are
active, which can be done without an eval.

_compgen_opt_words() {
  typeset -a words
  words=( ${~=1} )
  local find try
  find=${@[-1]}
  results=(${(M)words[@]:#$find*})
}

seems to work, unless I'm missing some basic ingredient.  If I'm not,
I'll commit this.

-- 
Peter Stephenson <pws@xxxxxxx>            Software Engineer
Tel: +44 (0)1223 692070                   Cambridge Silicon Radio Limited
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