13.3 The racket/load Language

► |  | Reference: Racket

1 | Language Model
2 | Syntactic Forms
3 | Datatypes
4 | Structures
5 | Classes and Objects
6 | Units
7 | Contracts
8 | Pattern Matching
9 | Control Flow
10 | Concurrency
11 | Macros
12 | Input and Output
13 | Reflection and Security
14 | Operating System
15 | Memory Management
16 | Unsafe Operations
17 | Running Racket
| Bibliography
| Index

▼ | 13 | Reflection and Security

13.1 | Namespaces
13.2 | Evaluation and Compilation
13.3 | The racket/ load Language
13.4 | Module Names and Loading
13.5 | Proxies and Chaperones
13.6 | Security Guards
13.7 | Custodians
13.8 | Thread Groups
13.9 | Structure Inspectors
13.10 | Code Inspectors
13.11 | Sandboxed Evaluation

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#### 13.3`` The racket/load Language

#lang racket/load

The racket/load language supports evaluation where each top-level form in the module body is separately passed to eval in the same way as for load.

The namespace for evaluation shares the module registry with the racket/load module instance, but it has a separate top-level environment, and it is initialized with the bindings of racket. A single namespace is created for each instance of the racket/load module (i.e., multiple modules using the racket/load language share a namespace). The racket/load library exports only #%module-begin and #%top-interaction forms that effectively swap in the evaluation namespace and call eval.

For example, the body of a module using racket/load can include module forms, so that running the following module prints 5:

#lang racket/load
( module m racket/base
( provide x)
( define x 5))
( module n racket/base
( require 'm)
( display x))
( require 'n)

Definitions in a module using racket/load are evaluated in the current namespace, which means that load and eval can see the definitions. For example, running the following module prints 6:

#lang racket/load
( define x 6)
( display ( eval 'x))

Since all forms within a racket/load module are evaluated in the top level, bindings cannot be exported from the module using provide. Similarly, since evaluation of the module-body forms is inherently dynamic, compilation of the module provides essentially no benefit. For these reasons, use racket/load for interactive exploration of top-level forms only, and not for constructing larger programs.

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