#!/usr/bin/env bash # -*- coding: utf-8 -*- # region header # Copyright Torben Sickert (info["~at~"]torben.website) 16.12.2012 # License # ------- # This library written by Torben Sickert stands under a creative commons naming # 3.0 unported license. See https://creativecommons.org/licenses/by/3.0/deed.de # endregion # shellcheck disable=SC2016,SC2034,SC2155 # region import # NOTE: We cannot import the logging module to avoid a dependency cycle. # shellcheck source=./module.sh source "$(dirname "${BASH_SOURCE[0]}")/module.sh" # endregion # region variables declare -gr BL_ARRAY__DOCUMENTATION__=' This module implements utility functions concerning arrays. ' # endregion # region functions alias bl.array.contains=bl_array_contains bl_array_contains() { local -r __documentation__=' Checks if given item equals to one item in given array. >>> local a=(a b c) >>> bl.array.contains c "${a[@]}"; echo $? 0 >>> bl.array.contains b a b c; echo $? 0 >>> bl.array.contains d a b c; echo $? 1 ' local match="$1" shift local item for item ; do if [ "$match" = "$item" ]; then return 0 fi done return 1 } alias bl.array.filter=bl_array_filter bl_array_filter() { local -r __documentation__=' Filters values from given array by given regular expression. >>> local a=(one two three wolf) >>> local b=( $(bl.array.filter ".*wo.*" "${a[@]}") ) >>> echo ${b[*]} two wolf ' local -r pattern="$1" shift local element for element in "$@"; do echo "$element" done | \ command grep --extended-regexp "$pattern" } alias bl.array.get_index=bl_array_get_index bl_array_get_index() { local -r __documentation__=' Get index of value in an array >>> local a=(one two three) >>> bl_array_get_index one "${a[@]}" 0 >>> local a=(one two three) >>> bl_array_get_index two "${a[@]}" 1 >>> bl_array_get_index bar foo bar baz 1 ' local -r search_value="$1" shift local -ar array=("$@") local -i result=-1 local -i index for index in "${!array[@]}"; do if [ "${array[$index]}" = "$search_value" ]; then result="$index" fi done echo "$result" if (( result == -1 )); then return 1 fi } alias bl.array.reverse=bl_array_reverse bl_array_reverse() { local -r __documentation__=' Reverse given array. >>> bl.array.reverse >>> bl.array.reverse a a >>> bl.array.reverse "a b c" c b a ' local result='' local item for item in $1; do if [ "$result" = '' ]; then result="$item" else result="$item $result" fi done echo "$result" } alias bl.array.slice=bl_array_slice bl_array_slice() { local -r __documentation__=' Returns a slice of an array (similar to Python). One way to remember how slices work is to think of the indices as pointing between elements, with the left edge of the first character numbered `0`. Then the right edge of the last element of an array of length `n` has index `n`, for example: ``` +---+---+---+---+---+---+ | 0 | 1 | 2 | 3 | 4 | 5 | +---+---+---+---+---+---+ 0 1 2 3 4 5 6 -6 -5 -4 -3 -2 -1 ``` >>> local a=(0 1 2 3 4 5) >>> echo $(bl.array.slice 1:-2 "${a[@]}") 1 2 3 >>> local a=(0 1 2 3 4 5) >>> echo $(bl.array.slice 0:1 "${a[@]}") 0 >>> local a=(0 1 2 3 4 5) >>> [ -z "$(bl.array.slice 1:1 "${a[@]}")" ] && echo empty empty >>> local a=(0 1 2 3 4 5) >>> [ -z "$(bl.array.slice 2:1 "${a[@]}")" ] && echo empty empty >>> local a=(0 1 2 3 4 5) >>> [ -z "$(bl.array.slice -2:-3 "${a[@]}")" ] && echo empty empty >>> local a=(0 1 2 3 4 5) >>> [ -z "$(bl.array.slice -2:-2 "${a[@]}")" ] && echo empty empty Slice indices have useful defaults; an omitted first index defaults to zero, an omitted second index defaults to the size of the string being sliced. >>> local a=(0 1 2 3 4 5) >>> # from the beginning to position 2 (excluded) >>> echo $(bl.array.slice 0:2 "${a[@]}") >>> echo $(bl.array.slice :2 "${a[@]}") 0 1 0 1 >>> local a=(0 1 2 3 4 5) >>> # from position 3 (included) to the end >>> echo $(bl.array.slice 3:"${#a[@]}" "${a[@]}") >>> echo $(bl.array.slice 3: "${a[@]}") 3 4 5 3 4 5 >>> local a=(0 1 2 3 4 5) >>> # from the second-last (included) to the end >>> echo $(bl.array.slice -2:"${#a[@]}" "${a[@]}") >>> echo $(bl.array.slice -2: "${a[@]}") 4 5 4 5 >>> local a=(0 1 2 3 4 5) >>> echo $(bl.array.slice -4:-2 "${a[@]}") 2 3 If no range is given, it works like normal array indices. >>> local a=(0 1 2 3 4 5) >>> echo $(bl.array.slice -1 "${a[@]}") 5 >>> local a=(0 1 2 3 4 5) >>> echo $(bl.array.slice -2 "${a[@]}") 4 >>> local a=(0 1 2 3 4 5) >>> echo $(bl.array.slice 0 "${a[@]}") 0 >>> local a=(0 1 2 3 4 5) >>> echo $(bl.array.slice 1 "${a[@]}") 1 >>> local a=(0 1 2 3 4 5) >>> bl.array.slice 6 "${a[@]}"; echo $? 1 >>> local a=(0 1 2 3 4 5) >>> bl.array.slice -7 "${a[@]}"; echo $? 1 ' local -i array_length local end local -i length local start if [[ "$1" == *:* ]]; then IFS=':' read -r start end <<< "$1" shift array_length="$#" # defaults [ -z "$end" ] && end=$array_length [ -z "$start" ] && start=0 (( start < 0 )) && \ (( start = array_length + start )) (( end < 0 )) && \ (( end = array_length + end )) else start="$1" shift array_length="$#" (( start < 0 )) && \ (( start = array_length + start )) (( end = start + 1 )) fi (( length = end - start )) (( start < 0 )) && \ return 1 # check bounds (( length < 0 )) && \ return 1 (( start < 0 )) && \ return 1 (( start >= array_length )) && \ return 1 # parameters start with $1, so add 1 to $start (( start = start + 1 )) echo "${@: $start:$length}" } alias bl.array.unique=bl_array_unique bl_array_unique() { local -r __documentation__=' Removes duplicates in given array. >>> bl.array.unique "" >>> bl.array.unique 1 1 >>> bl.array.unique "1 2 3" 1 2 3 >>> bl.array.unique "1 1 2 3" 1 2 3 >>> bl.array.unique "1 1 2 1 3" 1 2 3 >>> bl.array.unique "1 11 2 3" 1 11 2 3 ' echo "$1" | \ tr ' ' '\n' | \ sort --unique | \ tr '\n' ' ' } # endregion # region vim modline # vim: set tabstop=4 shiftwidth=4 expandtab: # vim: foldmethod=marker foldmarker=region,endregion: # endregion