2.5.21 readable-snip<%>

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► | 2 | Reference

2.1 | Windowing Classes
2.2 | Windowing Functions
2.3 | Drawing Classes
2.4 | Drawing Functions
2.5 | Editor Classes
2.6 | Editor Functions
2.7 | WXME Decoding

▼ | 2.5 | Editor Classes

2.5.1 | add-color<%>
2.5.2 | editor<%>
2.5.3 | editor-admin%
2.5.4 | editor-canvas%
2.5.5 | editor-data%
2.5.6 | editor-data-class%
2.5.7 | editor-data-class-list<%>
2.5.8 | editor-snip-editor-admin<%>
2.5.9 | editor-snip%
2.5.10 | editor-stream-in%
2.5.11 | editor-stream-in-base%
2.5.12 | editor-stream-in-bytes-base%
2.5.13 | editor-stream-out%
2.5.14 | editor-stream-out-base%
2.5.15 | editor-stream-out-bytes-base%
2.5.16 | editor-wordbreak-map%
2.5.17 | image-snip%
2.5.18 | keymap%
2.5.19 | mult-color<%>
2.5.20 | pasteboard%
2.5.21 | readable-snip<%>
2.5.22 | snip%
2.5.23 | snip-admin%
2.5.24 | snip-class%
2.5.25 | snip-class-list<%>
2.5.26 | string-snip%
2.5.27 | style<%>
2.5.28 | style-delta%
2.5.29 | style-list%
2.5.30 | tab-snip%
2.5.31 | text%

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read-special

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readable-snip<%> : interface?

A readable-snip<%> object is treated specially by the port generated by open-input-text-editor: When a readable-snip<%> object is encountered for the input stream, its read-special method is called to generate the read result for the snip, which is returned from the port as a “special” value in the sense of read-char-or-special.

Since read and read-syntax build on read-char-or-special, a snip can implement readable-snip<%> so that it produces a whole S-expression or some other kind of value when read is used on a stream containing the snip.

( send a-readable-snip read-special |  | source |  |  |  |
|  | line |  |  |  |
|  | column |  |  |  |
|  | position) |  | → |  | any/c

source : any/c
line : ( or/c exact-nonnegative-integer? false/c)
column : ( or/c exact-nonnegative-integer? false/c)
position : ( or/c exact-nonnegative-integer? false/c)

The arguments are the same as the arguments to a procedure returned by a custom input port’s read-in; see Custom Ports for details. The result is also the same as the result from a read-in-produced procedure.
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