[Nottingham] Bash Variables

[Mike Haber]

Hi All,
Just had a query from a colleague that I can't answer and is
interesting.

When using bash and exporting variables, is there a way of listing the
previous values that a variable contained?

For example if a script is run that contains 'export foo=bar' can the
previous values for $foo be accessed after the script has run?

Thanks
Mike 

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