[bash scripting] `contains_item` bash function. Check if an item is in an array

	#############################################################################
	# contains_item ${needle} ${haystack[@]}
	#############################################################################
	contains_item() {
	set +x
	local ITEM=$1
	local LIST=${@:2}

	for ELEM in ${LIST[@]}
	do
	#echo "Scanning for needle:${ITEM}: currently @ ${ELEM}"
	if [ ${ITEM} == ${ELEM} ]; then
	#echo "Found ${ITEM} == ${ELEM}"
	return 0
	fi
	done
	#echo "Did not find ${ITEM}"
	return 1
	}
	#############################################################################
	#
	# Example: We want to populate --enable-decoder= and --disable-decoder= flags
	# to invoke a ./configure script, the script gives us the list of all decoders available
	# we we want to exclude the ones in a given list
	#
	# ENABLED_DECODERS=(flv h263 h263i h264 hevc mpeg1video mpeg2video mpeg4 svq1 svq3 vp6 vp8 vp9 wmv1 wmv2 aac ac3 flac mp3 mp3 vorbis wmav1 wmav2 adpcm_g726)
	# AVAILABLE_DECODERS=`./configure --list-decoders` # We get all the available decoders
	#
	# DISABLED_DECODERS_FLAGS="" # We'll store the final decoders to disable here
	#
	# for DECODER in ${AVAILABLE_DECODERS}
	# do
	# ENCODER_ENABLED=`contains_item ${DECODER} ${ENABLED_DECODERS[@]}`
	# # if we don't find it in the enabled list, we add it.
	# # (Yes, in bash 1 stands for false. functions return 0 when everything went fine as in errors)
	# if [[ ${ENCODER_ENABLED} == 1 ]]; then
	# echo "Disabling not found decoder: ${DECODER}"
	# DISABLED_DECODERS_FLAGS+="--disable-decoder=${DECODER} ";
	# fi
	# done;

by GitHub

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