Brace Expansion

With brace expansion, we can generate arbitrary strings

• similar to filename expansion (ex. *.env), except the generated strings actually need to exist.

To be a proper brace expansion, there must be opening and closing braces, and at least one ,

$ echo a{d,c,b}e
# ade ace abe

Brace expansion is performed before any other expansions, and any characters special to other expansions are preserved in the result

• Bash does not apply any syntactic interpretation to the context of the expansion or the text between the braces.

Alpha example

$ ls
alpha.py alphabeta.py

### Brace expansion
$ mv alpha{,beta}.py ../