highlightLines

Returns the theme-independent highlight of code split into lines, with spans carrying tree-sitter capture names from language. Style a line with toAnnotatedString.

Lines are separated by \n only. One trailing \r is stripped from each line, so CRLF input yields the same text and numbering as LF input. There is no line after a final \n.

lineRanges selects lines by 1-based, inclusive ranges; null selects every line. Ranges are clipped to the existing lines and overlapping or adjacent ranges are merged, so each selected line is returned once, in ascending order. When the selection is empty, nothing is parsed and an empty list is returned.

Syntax errors in code never throw; the grammar's error recovery still yields captures for the parts it understood. On JVM and Android, native library loading failures are not caught here: they surface at the first access of Languages.<Name> as ExceptionInInitializerError, and on later accesses as NoClassDefFoundError. Both are LinkageErrors.

This function is pure and holds no shared state, so it can be called concurrently, for example from Dispatchers.Default. It constructs a fresh tree-sitter Parser on every call.