72 lines
2.2 KiB
Scheme
72 lines
2.2 KiB
Scheme
#reader(lib "scribble/reader.ss")
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#lang scheme/base
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(require "common.ss"
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scribble/decode
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(for-label lang/htdp-beginner-abbr))
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(provide prim-nonterms
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schemegrammar*+library
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schemegrammar*+qq)
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(define ex-str "This is a string with \" inside")
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(define-syntax-rule (schemegrammar*+library form ...)
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(schemegrammar*
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form ...
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(...
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[libray-require #, @scheme[(require string)]
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#, @scheme[(require (lib string string ...))]
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#, @scheme[(require (planet string package))]])
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(...
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[package #, @scheme[(string string number number)]])))
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(define-syntax-rule (schemegrammar*+qq form ...)
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(schemegrammar*+library
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form ...
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(...
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[quoted id
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number
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string
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character
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#, @scheme[(quoted ...)]
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#, @elem{@schemevalfont{'}@scheme[quoted]}
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#, @elem{@schemevalfont{`}@scheme[quoted]}
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#, @elem{@schemefont{,}@scheme[quoted]}
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#, @elem{@schemefont[",@"]@scheme[quoted]}])
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(...
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[quasiquoted id
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number
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string
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character
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#, @scheme[(quasiquoted ...)]
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#, @elem{@schemevalfont{'}@scheme[quasiquoted]}
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#, @elem{@schemevalfont{`}@scheme[quasiquoted]}
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#, @elem{@schemefont{,}@scheme[expr]}
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#, @elem{@schemefont[",@"]@scheme[expr]}])))
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(define prim-nonterms
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(make-splice
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(list
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@t{An @scheme[_id] is a sequence of characters not including a
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space or one of the following:}
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@t{@hspace[2] @litchar{"} @litchar{,} @litchar{'} @litchar{`}
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@litchar{(} @litchar{)} @litchar{[} @litchar{]}
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@litchar["{"] @litchar["}"] @litchar{|} @litchar{;}
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@litchar{#}}
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@t{A @scheme[_number] is a number such as @scheme[123], @scheme[3/2], or
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@scheme[5.5].}
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@t{A @scheme[_string] is enclosed by a pair of @litchar{"}. Unlike
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symbols, strings may be split into characters and manipulated by a
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variety of primitive functions. For example, @scheme["abcdef"],
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@scheme["This is a string"], and @scheme[#,ex-str] are all strings.}
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@t{A @scheme[_character] begins with @litchar{#\} and has the
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name of the character. For example, @scheme[#\a], @scheme[#\b],
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and @scheme[#\space] are characters.}
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)))
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