3.3 Literals: quote and #%datum

► |  | The Racket Reference

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
10 | Control Flow
11 | Concurrency and Parallelism
12 | Macros
13 | Input and Output
14 | Reflection and Security
15 | Operating System
16 | Memory Management
17 | Unsafe Operations
18 | Running Racket
| Bibliography
| Index

▼ | 3 | Syntactic Forms

3.1 | Modules: module, module*, ...
3.2 | Importing and Exporting: require and provide
3.3 | Literals: quote and #%datum
3.4 | Expression Wrapper: #%expression
3.5 | Variable References and #%top
3.6 | Locations: #%variable-reference
3.7 | Procedure Applications and #%app
3.8 | Procedure Expressions: lambda and case-lambda
3.9 | Local Binding: let, let*, letrec, ...
3.10 | Local Definitions: local
3.11 | Constructing Graphs: shared
3.12 | Conditionals: if, cond, and, and or
3.13 | Dispatch: case
3.14 | Definitions: define, define-syntax, ...
3.15 | Sequencing: begin, begin0, and begin-for-syntax
3.16 | Guarded Evaluation: when and unless
3.17 | Assignment: set! and set!-values
3.18 | Iterations and Comprehensions: for, for/ list, ...
3.19 | Continuation Marks: with-continuation-mark
3.20 | Quasiquoting: quasiquote, unquote, and unquote-splicing
3.21 | Syntax Quoting: quote-syntax
3.22 | Interaction Wrapper: #%top-interaction
3.23 | Blocks: block
3.24 | Internal-Definition Limiting: #%stratified-body
3.25 | Performance Hints: begin-encourage-inline
3.26 | Importing Modules Lazily: lazy-require

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quote
#%datum

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### 3.3 Literals: quote and #%datum🔗ℹ

Many forms are implicitly quoted (via #%datum) as literals. See Expansion Steps for more information.

> > > Quoting: quote and ’ in The Racket Guide introduces quote.

> syntax (quote datum)

Produces a constant value corresponding to datum (i.e., the representation of the program fragment) without its lexical information, source location, etc. Quoted pairs, vectors, and boxes are immutable.

Examples:

> > (quote x)
> 'x
> > (quote (+ 1 2))
> '(+ 1 2)
> > (+ 1 2)
> 3

> syntax (#%datum . datum)

Expands to (quote datum), as long as datum is not a keyword. If datum is a keyword, a syntax error is reported.

See also Expansion Steps for information on how the expander introduces #%datum identifiers.

Examples:

> > (#%datum . 10)
> 10
> > (#%datum . x)
> 'x
> > (#%datum . #:x)
> eval:6:0: #%datum: keyword misused as an expression
> at: #:x

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