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pkaramol
Asked: 2017-08-27 02:03:29 +0800 CST

shell - brace expansion not working

  • 772

I am trying the following script:

#!/bin/bash

printf "Hello, this is a demo of brace expansion\n"

echo "Hello to each one of t{i,a,o}k"

output:

$ ./hello.sh 
Hello, this is a demo of brace expansion
Hello to each one of t{i,a,o}k

why?

using 

GNU bash, version 4.3.48(1)-release (x86_64-pc-linux-gnu)
command-line

1 Answers

  1. Best Answer

    Double quotes suppress brace expansion:

    $ echo Hello t{i,a,o}k
Hello tik tak tok
$ echo "Hello t{i,a,o}k"
Hello t{i,a,o}k

    You can quote the rest of your expression. Possibly usefully, if you quote the space before the brace part it stops wordsplitting, so you get something like:

    $ echo "Hello "t{i,a,o}k
Hello tik Hello tak Hello tok
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