35 lines
1.3 KiB
Racket
35 lines
1.3 KiB
Racket
#lang scribble/doc
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@(require "common.ss")
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@definterface/title[readable-snip<%> ()]{
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A @scheme[readable-snip<%>] object is treated specially by the port
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generated by @scheme[open-input-text-editor]: When a
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@scheme[readable-snip<%>] object is encountered for the input stream,
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its @method[readable-snip<%> read-special] method is called to
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generate the read result for the snip, which is returned from the
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port as a ``special'' value in the sense of
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@scheme[read-char-or-special].
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Since @scheme[read] and @scheme[read-syntax] build on
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@scheme[read-char-or-special], a snip can implement
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@scheme[readable-snip<%>] so that it produces a whole S-expression or
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some other kind of value when @scheme[read] is used on a stream
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containing the snip.
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@defmethod[(read-special [source any/c]
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[line (or/c exact-nonnegative-integer? false/c)]
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[column (or/c exact-nonnegative-integer? false/c)]
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[position (or/c exact-nonnegative-integer? false/c)])
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any/c]{
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The arguments are the same as the arguments to a procedure returned by
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a custom input port's @scheme[_read-in]; see @secref[#:doc '(lib
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"scribblings/reference/reference.scrbl") "customport"] for
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details. The result is also the same as the result from a
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@scheme[_read-in]-produced procedure.
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}}
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