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Concepts
This section of the documentation covers the use of Objects, Libraries and References, Notations, Styles and Types and how each is created, edited and used in the Sym application.
Objects
An object is the basic building block of all of the symbolic content contained in a document - every term in every symbolic expression in Sym is an instance of an object. Many of the objects used in Sym have an object definition that specifies how the object looks and behaves, but it's also possible to create objects that don't have object definitions. All objects are identified by their name and object names are always defined in a specific namespace. All object definitions contain a type definition. Optionally, objects can also contain Properties, Clauses, Renderings, and a Description.
Autogenerated Objects
The Autogenerated Objects Library
The Autogenerated Objects library is populated during the build process. The list of object modules and objects in the Autogenerated Objects library can be customized and extended.

Concepts
This section of the documentation covers the use of Objects, Libraries and References, Notations, Styles and Types and how each is created, edited and used in the Sym application.
- Objects
  An object is the basic building block of all of the symbolic content contained in a document - every term in every symbolic expression in Sym is an instance of an object. Many of the objects used in Sym have an object definition that specifies how the object looks and behaves, but it's also possible to create objects that don't have object definitions. All objects are identified by their name and object names are always defined in a specific namespace. All object definitions contain a type definition. Optionally, objects can also contain Properties, Clauses, Renderings, and a Description.
  - Object Modules
    An Object Module contains object definitions. Object definitions contain the name, type definition, renderings, code and properties that define the functionality of every object. Object Modules are created, edited and managed using the Document Explorer.
  - Creating and Editing Objects
  - Objects Used in Code
    Objects that are commonly used in clauses in function are listed below.
  - Property Objects
  - Special Objects
  - Autogenerated Objects
    - The Autogenerated Objects Library
      The Autogenerated Objects library is populated during the build process. The list of object modules and objects in the Autogenerated Objects library can be customized and extended.
    - Functions that Generate Object Definitions
      A library can include functions that generate a list of object definitions. These functions can be configured so that they are executed as part of the build process and the object definitions that are returned are collected in the Autogenerated Objects library. Examples include the list of Colors and a list of objects that represent each of the libraries currently loaded into the document.
  - Monoids
    Monoids are typically defined as a binary mapping that has an identity element and is associative. In the construction of the Sym application, we have taken an equivalent, but different approach to defining and handling monoids. It may be surprising to see something so fundamental defined in a non-standard way, so the reasoning for taking this approach is explained below.
- Library Locations and References
  Locations are used to manage groups of libraries and documents. The purpose of locations is to make documents portable from one machine to another. To do that, locations can be online as well as on your local machine. If a document references online libraries, the required libraries will be downloaded automatically when the document is opened.
- Notations and Rendering
  The purpose of notations is to make it possible to easily change the way expressions are displayed. Notations are assigned to Document Modules, Unit Test Modules and Object Modules. The notation assigned determines which renderings are selected for each expression in the module.
- Styles
  Each notation refers to a stylesheet. Stylesheets define Styles. Styles are used in two places. First, they can be used to style text. Second, they can be used to style parts of an expression in a rendering. You can create new style and new stylesheets.
- Types
  Every term in every expression in a Sym document has a type assigned to it. Every object definition has a type definition as one of its components. Since type definitions can include things like type variables, Sym uses a type inferencing process to determine the explicit types assigned to each term in every expression.

The Autogenerated Objects Library

The Autogenerated Objects library is populated during the build process. The list of object modules and objects in the Autogenerated Objects library can be customized and extended.

Objects typically built in the Autogenerated Objects library include:

Colors
Namespaces,
Libraries
Built in functions
Built in types

Objects that would have appeared in the Autogenerated Objects but are already defined somewhere else in the referenced libraries are not generated. For example, most of the built in functions have object definitions in the Code.eql library. As a result, they don't appear in the Autogenerated Objects library.

This design makes it easy, for example, to add a rendering to an autogenerated object. Just copy and paste the object definition into another library, then add the rendering and build the document (F6). The object you modified should no longer appear in the Autogenerated Objects library.

The functions that generate the objects described here are built in functions. It's also possible to define new functions that generate object definitions and to extend the modules and objects included in the Autogenerated Objects library.