mirror of https://github.com/n-hys/bash.git
64 lines
1.5 KiB
Plaintext
64 lines
1.5 KiB
Plaintext
# This program is free software: you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation, either version 3 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program. If not, see <http://www.gnu.org/licenses/>.
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#
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# nameref variables as for loop index variables are special
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v1=1
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v2=2
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# simple for loop
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for v in v1 v2
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do
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typeset -n ref=$v
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echo $ref
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done
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unset v
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set -- first second third fourth fifth
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# unless you put a ${!v} in the for loop, ksh93 misbehaves
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typeset -n v=v1
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for v in v1 v2; do
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echo "${!v}: $v"
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done
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unset v
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# example cribbed from ksh93 o'reilly book
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first="I am first"
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second="I am in the middle"
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third="I am last"
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typeset -n ref=first
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for ref in first second third ; do
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echo "ref -> ${!ref}, value: $ref"
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done
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echo final state: "ref -> ${!ref}, value: $ref"
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readonly one=1
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readonly two=2
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readonly three=3
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typeset -n ref=one
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for ref in one two three; do
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echo "ref -> ${!ref}, value: $ref"
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done
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echo final state: "ref -> ${!ref}, value: $ref"
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unset ref
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typeset -n ref=one
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readonly ref
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for ref in one two three; do
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echo "ref -> ${!ref}, value: $ref"
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done
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echo final state: "ref -> ${!ref}, value: $ref"
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