GGUI/Public/TextBuffer.h file

TextBuffer: editable UTF-8 text stored as a piece table.

The original text and everything typed since are kept as two append-only stores; the document is a list of pieces referring into them. An edit changes the list, never the bytes, so it costs in proportion to the edit, not the document.

Positions   byte offsets into the current text
Anchors     positions that survive edits made by anyone: carets, selection ends, decoration
            ends, IME composition
Edits       transactions: a set of replacements applied and undone together
Undo        per buffer; adjacent typing and adjacent deletes merge into one step
Lines       an index of line starts, maintained by every edit

Not thread-safe: use on the thread that updates the document showing it.

Namespaces

namespace GGUI

Classes

struct GGUI::TextAnchor

Handle to an anchor. Only valid with the buffer that created it.

struct GGUI::TextEdit

Replace [Start, End) with Text. Start == End inserts; empty Text deletes.

struct GGUI::TextChange

Lines affected by a transaction: LinesBefore lines from FirstLine became LinesAfter.

class GGUI::TextBuffer

Editable UTF-8 text with anchors, undo, and a line index. See the file description.