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1.1 Pages

Schematics and symbols are presented as different types of document to the user, with different file extensions, icons and mime-types. However, when they are loaded into a gEDA application such as gschem for editing, they are internally represented in exactly the same way, by the page type. The page is the top-level gEDA document data type.

Internally, the main difference between a page for a schematic and a page for a symbol is the types of schematic element they are permitted to contain (see Objects). For example, a symbol is not permitted to contain nets, buses, or instances of other symbols, and a schematic is not permitted to contain pins.

Note: Although the restrictions on what types of primitive element schematics and symbols may contain are not enforced by the API, designs which violate these restrictions may cause the netlister not to work as expected.

Each page is associated with a filename, although the filename is not required by the API either to be valid or to be associated with a accessible file in the filesystem.

Pages are not garbage-collected; once you create a page, you are responsible for making sure that it is disposed of when it is no longer required.