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From: Lew Pitcher <lew.pitcher@digitalfreehold.ca>
Newsgroups: comp.unix.shell
Subject: Re: What does @{FOOBAR@a} mean? (bash)
Date: Sun, 14 Apr 2024 14:11:06 -0000 (UTC)
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On Sun, 14 Apr 2024 06:07:12 -0400, Popping Mad wrote:

> On 4/13/24 18:14, Lew Pitcher wrote:
>> The expansion is a string consisting of flag values
>>                      representing parameter's attributes.
> 
> 
> What does this mean?

bash expansion variables have various (and multiple) characteristics that
govern how they work in expansions. You can have <<functions>> or
<<non-functions>>, <<indexed arrays>> or <<associative arrays>> or
<<integers>>, <<exported>> or <<not exported>>, etc.

You can use the "typeset" builtin[1] to explicitly set these characteristics,
or set them by your bash script actions.

The "typeset" builtin can also tell you what those characteristics are for
specific expansion variables.

Apparently, bash has now added an expansion rule that /also/ reports on the
characteristics of the expansion variable.


[1] See bash(1) SHELL BUILTIN COMMANDS for more details

HTH
-- 
Lew Pitcher
"In Skills We Trust"