copy
Brace expansions are commonly used with the cp or mv commands in order to dynamically generate strings. In this lesson, we'll use a brace expansion to shorten a command like cp index.js index.js.backup to cp index.js{,.backup}. We'll also see how brace expansions can generate sequences. For example, touch test-{1..10} will generate the arguments to touch to create 10 test files.
Note that the tree command that I use in this lesson has to be installed.
Case 0:
It acts like a loop
echo pre-{a,b,c}-post
## pre-a-post pre-b-post pre-c-post
echo pre-{,b,c}-post
## pre--post pre-b-post pre-c-post
echo {1..10}
## 1 2 3 4 5 6 7 8 9 10
echo {a..z}
## a b c d e f g h i j k l m n o p q r s t u v w x y z
Case 1:
copy index.js
and create a backup file called index.js.backup
cp index.js{,.backup}
Case 2:
Create multi nested folder with same structure
mkdir -p packages/{pkg1,pkg2,pkg3}/src
tree
Case 3:
Greate multi test files
touch test-{1..3}.js
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