Use the builtin ':' bash command to increment variables

[ $V ] || : $((V++)) && echo $V
I just found another use for the builtin ':' bash command. It increments counters for me in a loop if a certain condition is met... : [arguments] No effect; the command does nothing beyond expanding arguments and performing any specified redirections. A zero exit code is returned.
Sample Output
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By: axelabs
2012-06-15 16:48:03

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  • don't `man bash` Show Sample Output


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    help builtin
    kev · 2011-12-25 04:52:49 2
  • Similar to xargs -i, but works with builtin bash commands (rather than running "bash -c ..." through xargs)


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    xargsb() { while read -r cmd; do ${@//'{}'/$cmd}; done; }
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What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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