Structure editor

A structure editor, also structured editor or projectional editor, is any document editor that is cognizant of the document’s underlying structure. Structure editors can be used to edit hierarchical or marked up text, computer programs, diagrams, chemical formulas, and any other type of content with clear and well-defined structure. In contrast, a text editor is any document editor used for editing plain text files. A structure editor, also structured editor or projectional editor, is any document editor that is cognizant of the document’s underlying structure. Structure editors can be used to edit hierarchical or marked up text, computer programs, diagrams, chemical formulas, and any other type of content with clear and well-defined structure. In contrast, a text editor is any document editor used for editing plain text files. Typically, the benefits of text and structure editing are combined in the user interface of a single hybrid tool. For example, Emacs is fundamentally a text editor, but supports the manipulation of words, sentences, and paragraphs as structures that are inferred from the text. Conversely, Dreamweaver is fundamentally a structure editor for marked up web documents, but supports the display and manipulation of raw HTML text as well. Similarly, molecule editors typically support both graphical and textual input. Structure editing predominates when content is graphical and textual representations are awkward, e.g., CAD systems and PowerPoint. Text editing predominates when content is largely devoid of structure, e.g., text fields in web forms. WYSIWYG word processing systems such as Word, which appear to edit formatted text directly, are essentially structure editors for the underlying marked-up text. In linguistics, syntax is the study of the structure of grammatical utterances, and accordingly syntax-directed editor is a synonym for structure editor. Language-based editor and language-sensitive editor are also synonyms. A language-based editor’s features may be implemented by ad hoc code or by a formal grammar. For example, language sensitivity in Emacs is implemented in the Lisp definition of the edit mode for the given language. In contrast, language sensitivity in an XML editor is driven by a formal DTD schema for the given language.