More Conditional Logic in Ruby!

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Tutorial Difficulty Level

Following from the previous tutorial on Conditional Logic in Ruby, look at this example:

# Let the user guess.
print "Enter heads or tails? "
hort = gets.chomp
unless hort == 'heads' || hort == 'tails' 
    print "I _said_ heads or tails.  Can't you read?\n"
    exit(1)
end

# Now toss the coin.
toss = if rand(2) == 1 then
    "heads"
else
    "tails"
end

# Report.
print "Toss was ", toss, ".\n"
print "You Win!\n" if hort == toss

Some more amazing if lore:

The unless keyword is like if, but uses the opposite sense of the test: The code is run if the test is false.
As with many things in Ruby, if may look like a statement, but it is actually an expression, with a return value.
The if has a postfix form where the condition comes last. This works with unless as well.

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