[Help-bash] What is the regex for bash variable names?

[Peng Yu]

Hi, I'd like to know the exact definition of a bash variable name in
terms of regex. Is this documented somewhere? Thanks.

[Greg Wooledge]

Post by Peng Yu
Hi, I'd like to know the exact definition of a bash variable name in
terms of regex. Is this documented somewhere? Thanks.

name A word consisting only of alphanumeric characters and under‐
scores, and beginning with an alphabetic character or an under‐
score. Also referred to as an identifier.

[Chet Ramey]

Post by Greg Wooledge

Post by Peng Yu
Hi, I'd like to know the exact definition of a bash variable name in
terms of regex. Is this documented somewhere? Thanks.

name A word consisting only of alphanumeric characters and under‐
scores, and beginning with an alphabetic character or an under‐
score. Also referred to as an identifier.

Technically, you have to add "from the portable character set" like Posix
does. Bash doesn't allow variable names that contain non-ASCII characters
that might be alphabetics in the current locale.