Overcome Bash's expansion order
mkdir test{1,2,3,4,5,6,7,8,9,10}
something extremely boring to type! Why not use seq?
seq -s, 1 10
and use its output inside the curly braces?
The obvious solution
mkdir test{$(seq -s, 1 10)}
is, unfortunately, too naive and doesn't work. The answer is the order of the shell expansions (feature of Bourne Shell, actually), where brace expansion happens before command substitution (according to Bash's manual).
The solution is to put another level of substitution, using the powerful and mystic command eval.
I found the trick in a similar problem in the post at http://stackoverflow.com/questions/6549037/bash-brace-expansion-in-scripts-not-working-due-to-unwanted-escaping
1 Alternatives + Submit Alt
-
no need for seq or eval
-3mkdir ${1..10}
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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mkdir test{1..10} works fineseq -s, 1 4 1000How, are you going to write it? Or, let's say you're creating the directories "lonely", "closely", "finally" and all these names are stored in a shell variable, or can be extracted from another program. The numbers here are just an example. A simple, and maybe not very suitable, example. They don't really have any special meaning.echo {1..100..4},