Reference: PLT Scheme

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`` | Running PLT Scheme
| Bibliography
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unit-static-signatures
signature-members

Version: 4.0.2
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#### 6.11`` Transformer Helpers

(require scheme/unit-exptime)

The scheme/unit-exptime library provides procedures that are intended for use by macro transformers. In particular, the library is typically imported using for-syntax into a module that defines macro with define-syntax.

(unit-static-signatures |  | unit-identifier |
|  | err-syntax) |

→

(list/c (cons/c (or/c symbol? false/c)
identifier?))

(list/c (cons/c (or/c symbol? false/c)
identifier?))

unit-identifier : identifier?
err-syntax : syntax?

If unit-identifier is bound to static unit information via define-unit (or other such forms), the result is two values. The first value is for the unit’s imports, and the second is for the unit’s exports. Each result value is a list, where each list element pairs a symbol or #f with an identifier. The symbol or #f indicates the import’s or export’s tag (where #f indicates no tag), and the identifier indicates the binding of the corresponding signature.

If unit-identifier is not bound to static unit information, then the exn:fail:syntax exception is raised. In that case, the given err-syntax argument is used as the source of the error, where unit-identifer is used as the detail source location.

(signature-members |  | sig-identifier |  |  |  |

err-syntax)

→

(or/c identifier? false/c)
(listof identifier?)
(listof identifier?)
(listof identifier?)

sig-identifier : identifier?
err-syntax : syntax?

If sig-identifier is bound to static unit information via define-signature (or other such forms), the result is four values:

- an identifier or #f indicating the signature (of any) that is extended by the sig-identifier binding;

- a list of identifiers representing the variables supplied/required by the signature;

- a list of identifiers for variable definitions in the signature (i.e., variable bindings that are provided on import, but not defined by units that implement the signature); and

- a list of identifiers with syntax definitions in the signature.

If sig-identifier is not bound to a signature, then the exn:fail:syntax exception is raised. In that case, the given err-syntax argument is used as the source of the error, where sig-identifier is used as the detail source location.

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