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typesetting/quad/qtest/mds/module-provide.md

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# Exports: `provide`
By default, all of a modules definitions are private to the module. The
`provide` form specifies definitions to be made available where the
module is `require`d.
```racket
(provide provide-spec ...)
```
A `provide` form can only appear at module level \(i.e., in the
immediate body of a `module`\). Specifying multiple `provide-spec`s in
a single `provide` is exactly the same as using multiple `provide`s each
with a single `provide-spec`.
Each identifier can be exported at most once from a module across all
`provide`s within the module. More precisely, the external name for each
export must be distinct; the same internal binding can be exported
multiple times with different external names.
The allowed shape of a `provide-spec` is defined recursively:
```racket
identifier
```
In its simplest form, a `provide-spec` indicates a binding within its
module to be exported. The binding can be from either a local
definition, or from an import.
```racket
(rename-out [orig-id export-id] ...)
```
A `rename-out` form is similar to just specifying an identifier, but the
exported binding `orig-id` is given a different name, `export-id`, to
importing modules.
```racket
(struct-out struct-id)
```
A `struct-out` form exports the bindings created by `(struct struct-id
....)`.
> +See \[missing\] for information on `define-struct`.
```racket
(all-defined-out)
```
The `all-defined-out` shorthand exports all bindings that are defined
within the exporting module \(as opposed to imported\).
Use of the `all-defined-out` shorthand is generally discouraged, because
it makes less clear the actual exports for a module, and because Racket
programmers get into the habit of thinking that definitions can be added
freely to a module without affecting its public interface \(which is not
the case when `all-defined-out` is used\).
```racket
(all-from-out module-path)
```
The `all-from-out` shorthand exports all bindings in the module that
were imported using a `require-spec` that is based on `module-path`.
Although different `module-path`s could refer to the same file-based
module, re-exporting with `all-from-out` is based specifically on the
`module-path` reference, and not the module that is actually referenced.
```racket
(except-out provide-spec id ...)
```
Like `provide-spec`, but omitting the export of each `id`, where `id` is
the external name of the binding to omit.
```racket
(prefix-out prefix-id provide-spec)
```
Like `provide-spec`, but adding `prefix-id` to the beginning of the
external name for each exported binding.