13.3 The racket/load Language

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2 | Syntactic Forms
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6 | Units
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8 | Pattern Matching
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14 | Operating System
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▼ | 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 | Impersonators 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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