Code Editor

Problem

Every keystroke must update highlighting, folding, and diagnostics in milliseconds on large files.

Why tree-sitter.zig helps

One long-lived Parser plus per-keystroke InputEdits keeps reparse work proportional to the edit. Reuse counters (reused_node_count) let you verify the budget in production.

API

Parser (reused), InputEdit, Tree, getChangedRanges, TreeCursor.

Architecture

Buffer → keystroke → InputEdit → parse(old, edit, text)
  → changed ranges → update faces/folds/diagnostics

Example

See Incremental: 1 + 2 → 1 + 22 reparses with a one-span diff.

Output

changed: bytes [4, 6]

Next steps

• Incremental Parsing, Performance
• IDE Language Tools