1.164.1 Instance variables

text_buffer <- editors: chain

Chain of editors associated to this text_buffer object. Whenever the text_buffer is text_buffer<-modified, the editor objects in text_buffer<-editors will be informed.

This variable is managed by text_buffer->attach and text_buffer->detach, called from editor->initialise, editor->unlink and editor->text_buffer. The methods text_buffer->attach and text_buffer->detach may be redefined to monitor attachments/detachments of editors. The redefinition must use object->send_super and may not fail.

text_buffer <- first_fragment: fragment*

First/last fragment in the double-linked list of fragments. Fragments in this list are kept ordered on fragment<-start. See also fragment<-next and fragment<-previous.

text_buffer <- generation: 0..

Integer that is incremented each time the text_buffer object has been changed. It is used by PceEmacs colourisation support to check whether the text-buffer has changed since the last time it was coloured. We cannot use the text_buffer<->modified flag for that purpose as this reflects whether the content is different from the file or not.

Please note that this counter is only incremented; text_buffer->undo actions increment it too.

text_buffer <- last_fragment: fragment*

Inherits description from: text_buffer-first_fragment

text_buffer <- modified: bool

Indicate that the text_buffer has been modified. When the contents of this variable has changed, each associated editor will forwards its editor<-modified_message with the following arguments:

@receiver	editor<-master
@arg1	New value of text_buffer<-modified.

See also text_buffer<-generation.

See also

- editor-modified_message
- editor-editable

text_buffer-size: alien:int

Number of characters in the text_buffer. A character is defined as a Unicode code point. The method text_buffer<-length is available to avoid a conflict with editor<->size.

text_buffer <-> syntax: syntax_table

Description of the syntax. This table describes character categories, brackets, quotes, comment, sentences and paragraphs. See class syntax_table and notably syntax_table->syntax for details.

Initially this slot is filled with the built-in syntax_table object named default.

The text_buffer's text_buffer<-syntax table is used by many methods on class text_buffer and class editor to recognise words, matching braces, comment, etc. Syntax tables are used extensively by PceEmacs.

See also text_buffer<-scan, text_buffer->in_comment, text_buffer<-skip_comment, and text_buffer->for_all_comments

text_buffer <- undo_buffer_size: bytes=int

Size of the undo-buffer in characters. Larger values allow for more undo at the cost of more memory. The value 0 disables recording of undo information.