13.7.3 Special Comments

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1 | Language Model
2 | Notation for Documentation
3 | Syntactic Forms
4 | Datatypes
5 | Structures
6 | Classes and Objects
7 | Units
8 | Contracts
9 | Pattern Matching
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11 | Concurrency and Parallelism
12 | Macros
13 | Input and Output
14 | Reflection and Security
15 | Operating System
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► | 13 | Input and Output

13.1 | Ports
13.2 | Byte and String Input
13.3 | Byte and String Output
13.4 | Reading
13.5 | Writing
13.6 | Pretty Printing
13.7 | Reader Extension
13.8 | Printer Extension
13.9 | Serialization
13.10 | Fast-Load Serialization
13.11 | Cryptographic Hashing

▼ | 13.7 | Reader Extension

13.7.1 | Readtables
13.7.2 | Reader-Extension Procedures
13.7.3 | Special Comments

On this page:

make-special-comment
special-comment?
special-comment-value

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#### 13.7.3 Special Comments🔗ℹ

> procedure (make-special-comment v) → special-comment?
> v : any/c

Creates a special-comment value that encapsulates v. The read, read-syntax, etc., procedures treat values constructed with make-special-comment as delimiting whitespace when returned by a reader-extension procedure (see Reader-Extension Procedures).

> procedure (special-comment? v) → boolean?
> v : any/c

Returns #t if v is the result of make-special-comment, #f otherwise.

> procedure (special-comment-value sc) → any
> sc : special-comment?

Returns the value encapsulated by the special-comment value sc. This value is never used directly by a reader, but it might be used by the context of a read-char-or-special, etc., call that detects a special comment.
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