51 lines
1.6 KiB
Racket
51 lines
1.6 KiB
Racket
#lang scribble/doc
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@(require scribble/manual scribble/eval "guide-utils.rkt")
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@title{Simple Values}
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Racket values include numbers, booleans, strings, and byte strings. In
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DrRacket and documentation examples (when you read the documentation
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in color), value expressions are shown in green.
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@defterm{Numbers} are written in the usual way, including fractions
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and imaginary numbers:
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@moreguide["numbers"]{numbers}
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@racketblock[
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1 3.14
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1/2 6.02e+23
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1+2i 9999999999999999999999
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]
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@defterm{Booleans} are @racket[#t] for true and @racket[#f] for
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false. In conditionals, however, all non-@racket[#f] values are
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treated as true.
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@moreguide["booleans"]{booleans}
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@defterm{Strings} are written between doublequotes. Within a string,
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backslash is an escaping character; for example, a backslash followed
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by a doublequote includes a literal doublequote in the string. Except
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for an unescaped doublequote or backslash, any Unicode character can
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appear in a string constant.
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@moreguide["strings"]{strings}
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@racketblock[
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"Hello, world!"
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"Benjamin \"Bugsy\" Siegel"
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"\u03BBx:(\u03BC\u03B1.\u03B1\u2192\u03B1).xx"
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]
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When a constant is evaluated in the @tech{REPL}, it typically prints the same
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as its input syntax. In some cases, the printed form is a normalized
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version of the input syntax. In documentation and in DrRacket's @tech{REPL},
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results are printed in blue instead of green to highlight the
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difference between an input expression and a printed result.
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@examples[
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(eval:alts (unsyntax (racketvalfont "1.0000")) 1.0000)
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(eval:alts (unsyntax (racketvalfont "\"Bugs \\u0022Figaro\\u0022 Bunny\"")) "Bugs \u0022Figaro\u0022 Bunny")
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]
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