34 lines
488 B
Bash
34 lines
488 B
Bash
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init() {
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if [[ -n $KSH_VERSION ]]; then
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set -A stack
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else
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stack=(); # this sets stack to '()' in ksh
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fi
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}
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push() {
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stack=("$1" "${stack[@]}")
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}
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stack_top() {
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# this approach sidesteps zsh indexing difference
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set -- "${stack[@]}"
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printf '%s\n' "$1"
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}
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pop() {
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stack_top
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stack=("${stack[@]:1}")
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}
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empty() {
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(( ${#stack[@]} == 0 ))
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}
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# Demo
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push fred; push wilma; push betty; push barney
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printf 'peek(stack)==%s\n' "$(stack_top)"
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while ! empty; do
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pop
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done
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