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Join the content of a bash array with commas

Terminal - Join the content of a bash array with commas
printf "%s," "${LIST[@]}" | cut -d "," -f 1-${#LIST[@]}
2012-06-04 14:56:12
User: Valise
Functions: cut printf
0
Join the content of a bash array with commas

printf reapeats the format as longer as it has arguments. Then the idea is to make cut retain as much fields as we have elements in the array.

As usual with such join/split string manipulation, you have to make sure you don't have conflicts between your separator and your array content.

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
(IFS=,; echo "${array[*]}")
2013-09-25 10:36:38
User: aspiers
Functions: echo
2

This type of join is clearly documented in the bash manual. Only the first character of IFS is used for the delimiter.

printf -- " -e %s" ${ARRAY[*]}
2014-02-25 03:34:12
User: SEJeff
Functions: printf
1
DOCKER_APP_VARS=(DATABASE_USER=dbuserro, DATABASE_PASSWORD=maipass)

[jeff@omniscience container] (master)$ echo docker run $(printf -- " -e %s" ${DOCKER_APP_VARS[*]}) -name 12factorapp mattdm/fedora-small

docker run -e DATABASE_USER=dbuserro, -e DATABASE_PASSWORD=maipass -name 12factorapp mattdm/fedora-small

Note that the printf method by itsself doesn't include a newline (\n), so you'll need to embed it into an echo statement or something that does.

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