2021-07-29 00:37:35 -07:00
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#!/usr/bin/env sh
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# YES_ZSH
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2021-07-29 05:44:12 -07:00
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# YES_BASH
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# YES_DASH
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2021-07-29 00:37:35 -07:00
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2021-07-30 19:41:16 -07:00
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sum() { ### @-
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2021-08-01 07:09:21 -07:00
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### compute the summation of its arguments without forking processes.
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### this relies on the shell's built-in arithmetic operators.
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###
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### ```
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### $ sum 1 2 3
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### 6
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### ```
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###
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### **TODO:** consider renaming because sum(1) already exists.
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2021-07-29 00:37:35 -07:00
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local sum=0
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for i; do
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2021-07-29 10:40:15 -07:00
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: $((sum+=i))
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2021-07-29 00:37:35 -07:00
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done
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echo "$sum"
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}
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[ "${SOURCING:-0}" -gt 0 ] || sum "$@"
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