Scheme equality of returning value

Question

I'm at beginning with Scheme. I'm trying to check equality of returning boolean value

(cond [(= (Test number) #t) 1])]

If my test function returns true, my main function should return 1. But I get contract violation error. Is there anybody could help me?

score 1 · Accepted Answer · edited May 23 '17 at 12:05

= is only used to compare numbers. eq? would be the correct equality procedure if you really need to check if something really is #t.

Normally any value not #f is considered a true value and if that is ok you should do this:

(cond [(Test number) 1]
      [else 'else-case])

Your cond misses a default case, like the one I've added. In case your Test return #f you really need it or else the result is undefined.

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