Using the assigned value of a variable as a dynamic variable (unix)

I was in a situation where I had to find a simple way to a variable mapping.

The script whatIs would have to translate the received parameter into the predefined values within the script.

I wanted something straightforward, and didn't want to do a series of ifs to compare the contents.

The easiest solution I found was to simply use 'eval' to retrieve the matching value of the passed parameter and provide me with the correlated value.

whatIs:

orange="fruit"
potato="vegetable"
cod="fish"
eval "v=\$$1"
echo $v

Call script whatIs with parameter orange and the output will be the value assigned to orange in the script.

whatIs orange

> fruit

As for my use case, I would then use the output ( in this example: fruit ) as a variable name

and use in my program.

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