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Home > Forums > Programmers > Languages > Scheme Forum

Checking if a variable exists

Read More Threads Like This One

llangevi (Programmer)

28 Oct 99 7:24

Hi,
I am adding to an existing piece of code and was wondering if it is possible to check for the existence of a
variable. I found a command "symbol?" and was wondering if this was the proper use.

Thanks for your time and consideration in this matter.

Lou

duchan (Instructor)

1 Nov 99 7:03

I don't know how to do what I think you want. However, symbol? is not what you're looking for.
symbol? is a procedure that takes one argument and returns #t if the argument is a symbol, #f otherwise
Examples:

(symbol? 7) -->#f
(symbol? '(a b c)) -->#f
(symbol? 'bill) -->#t

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