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25 lines
601 B
Markdown
25 lines
601 B
Markdown
5 years ago
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# Booleans
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Racket has two distinguished constants to represent boolean values: `#t`
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for true and `#f` for false. Uppercase `#T` and `#F` are parsed as the
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same values, but the lowercase forms are preferred.
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The `boolean?` procedure recognizes the two boolean constants. In the
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result of a test expression for `if`, `cond`, `and`, `or`, etc.,
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however, any value other than `#f` counts as true.
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Examples:
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```racket
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> (= 2 (+ 1 1))
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#t
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> (boolean? #t)
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#t
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> (boolean? #f)
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#t
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> (boolean? "no")
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#f
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> (if "no" 1 0)
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1
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```
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