12.11File Inclusion🔗 i

A path-spec resembles a subset of the mod-path forms for require , but it specifies a file whose content need not be a module. That is, string refers to a file using a platform-independent relative path, (file string) refers to a file using platform-specific notation, and (lib string... ) refers to a file within a collection.

If path-spec specifies a relative path, the path is resolved relative to the source for the include expression, if that source is a complete path string. If the source is not a complete path string, then path-spec is resolved relative to (current-load-relative-directory ) if it is not #f, or relative to (current-directory ) otherwise.

The included syntax is given the lexical context of the include expression, while the included syntax’s source location refers to its actual source.

The reader-expr is evaluated at expansion time in the transformer environment. Since it serves as a replacement for read-syntax , the expression’s value should be a procedure that consumes two inputs—a string representing the source and an input port—and produces a syntax object or eof . The procedure will be called repeatedly until it produces eof .

The syntax objects returned by the procedure should have source location information, but usually no lexical context; any lexical context in the syntax objects will be ignored.