Re: Filtering an array

["S. Cowles" <scowles@xxxxxxxx>]

On Fri, 24 Feb 2012, Jesper Nygårds wrote:
> Date: Thu, 23 Feb 2012 23:11:29
> From: Jesper Nygårds <jesper.nygards@xxxxxxxxx>
> To: zsh-users@xxxxxxx
> Subject: Filtering an array
>
> I am scratching my head over getting something seemingly simple to work.
>
> I have written this function:
>
> findfiles() {
>    local myfiles myarg
>    myfiles=( **/*$1* )
>    shift
>    for myarg in $@; do
>        myfiles=${(M)myfiles:#*$myarg*}
>    done
>    print $myfiles
> }

jesper

this is my version of your function.  the biggest difference i see
between your function and my version (with regard to intent and
disregarding coding errors), is the initial expansion of ${myfiles}.
file selection in both versions is done by pattern matching, so i
did not use the same initial file list loading as yours

	myfiles=( **/*$1* )

to cause any subsetting; that step struck me as unneccessary.

also, your version redefines ${myfiles} in every instance of the for
loop; this never accummulates the pattern matches which is what i
thought was your objective.

if i misunderstood your requirements, i apologize.

the function shown here does give a correct list of unique files
matching the pattern[s] given on the invocation line.

usage:
	findfiles starting_sub_dir pat1 [pat2...]

findfiles(){
	# parameter declarations.
	typeset -a pats allfiles
	typeset -aU selection
	local srcdir pat
	# argument parsing and checking.
	srcdir=${1}
	if [[ ! -d ${srcdir} ]]
	then
		# bomb.
		return 1
	fi
	shift
	# patterns for which to search.
	pats=( $@ )
	# get all files (only files, including dot files) in specified
	# source directory.
	allfiles=( ${srcdir}/**/*(D,.) )
	# initialize the collection.
	selection=()
	# do the subsetting and collecting.
	for pat in ${pats}
	do
		selection=(
			${selection}
			# append any additional matches.
			${(M)allfiles:#*${pat}*}
		)
	done
	# report the results.
	print -l ${selection}
	# clean up.
	unset srcdir pat pats allfiles selection
}