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#!/usr/bin/env bash |
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# |
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# Constructs borrowed from ksh. Hm I didn't realize zsh also implements these! |
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# mksh implements most too. |
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|
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#### C-style for loop |
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n=10 |
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for ((a=1; a <= n ; a++)) # Double parentheses, and naked 'n' |
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do |
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if test $a = 3; then |
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continue |
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fi |
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if test $a = 6; then |
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break |
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fi |
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echo $a |
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done |
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## status: 0 |
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## STDOUT: |
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1 |
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2 |
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4 |
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5 |
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## END |
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|
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#### For loop with and without semicolon |
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for ((a=1; a <= 3; a++)); do |
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echo $a |
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done |
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for ((a=1; a <= 3; a++)) do |
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echo $a |
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done |
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## status: 0 |
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## STDOUT: |
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1 |
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2 |
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3 |
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1 |
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2 |
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3 |
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## END |
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|
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#### Accepts { } syntax too |
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for ((a=1; a <= 3; a++)) { |
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echo $a |
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} |
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## STDOUT: |
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1 |
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2 |
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3 |
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## END |
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|
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#### Empty init |
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i=1 |
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for (( ;i < 4; i++ )); do |
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echo $i |
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done |
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## status: 0 |
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## STDOUT: |
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1 |
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2 |
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3 |
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## END |
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|
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#### Empty init and cond |
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i=1 |
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for (( ; ; i++ )); do |
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if test $i = 4; then |
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break |
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fi |
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echo $i |
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done |
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## status: 0 |
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## STDOUT: |
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1 |
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2 |
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3 |
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## END |
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|
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#### Infinite loop with ((;;)) |
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a=1 |
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for (( ; ; )); do |
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if test $a = 4; then |
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break |
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fi |
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echo $((a++)) |
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done |
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## status: 0 |
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## STDOUT: |
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1 |
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2 |
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3 |
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## END |