# Homework #2: Problem 3
# This worksheet tests the procedure reverse, which reverses the order of lists and characters of a 
# string.
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# Input the definitions from procedure `reverse`.
> read reverse;
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# Test reverse with a list of numbers, words, and the null list.
> reverse([1,2,3,4]);

                                  [4, 3, 2, 1]
> reverse([one,two,three,four]);

                             [four, three, two, one]
>  reverse([]);

                                       []
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# Test reverse with a string.
> reverse(`This is a string`);

                                gnirts a si sihT
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# Test reverse with some invalid input.
> reverse(2*s);
Error, (in reverse) 2*s, is not a string or list

> reverse({1,2,3,4});
Error, (in reverse) {3, 4, 1, 2}, is not a string or list

> reverse(howdy-doo);
Error, (in reverse) howdy-doo, is not a string or list