3.1 Booleans

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▼ | 3 | Built-In Datatypes

3.1 | Booleans
3.2 | Numbers
3.3 | Characters
3.4 | Strings (Unicode)
3.5 | Bytes and Byte Strings
3.6 | Symbols
3.7 | Keywords
3.8 | Pairs and Lists
3.9 | Vectors
3.10 | Hash Tables
3.11 | Boxes
3.12 | Void and Undefined

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#### 3.1`` Booleans

Racket has two distinguished constants to represent boolean values: #t for true and #f for false. Uppercase #T and #F are parsed as the same values, but the lowercase forms are preferred.

The boolean? procedure recognizes the two boolean constants. In the result of a test expression for if, cond, and, or, etc., however, any value other than #f counts as true.

Examples:

> > (= 2 (+ 1 1))
> #t
> > (boolean? #t)
> #t
> > (boolean? #f)
> #t
> > (boolean? "no")
> #f
> > (if "no" 1 0)
> 1

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