Entities

An entity is a reusable fragment of the document content that can be reused multiple times by reference.

Unlike other editors, Serna allows you to edit entity references in-place and shows them as regular content.

There are two types of entities:
  1. Internal Entities

    An internal entity can be reused only in the document in which it was declared.

    Figure 1. Internal entity in the Editing Window and ContentMap.



  2. External Entities

    An external entity is saved to a separate file and can be reused in any document.

    Figure 2. External entity in the Editing Window and ContentMap.



Entity Declarations

Before an entity can be used, it must be declared. All entities are declared with the "ENTITY" declaration:
<!ENTITY legal-notice SYSTEM "legal-notice.xml">

Entities can be declared in a DTD file that is external to the edited document (the external DTD subset), or declared in the edited document (the internal DTD subset). The declarations of internal and external entities in the internal DTD subset can be changed and removed.

Symbols

Unicode symbols cannot usually be entered from the keyboard directly. Serna offers you the following ways to insert such symbols: