Re: Filtering an array

["S. Cowles" <scowles@ckhb.org>]

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On Fri, 24 Feb 2012, Jesper Nygårds wrote:
> Date: Thu, 23 Feb 2012 23:11:29
> From: Jesper Nygårds <jesper.nygards@gmail.com>
> To: zsh-users@zsh.org
> 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
}