27 lines
1.6 KiB
TypeScript
27 lines
1.6 KiB
TypeScript
/**
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* Little-endian primitives for reading the walk/snapshot wire buffers. Shared by
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* the hand-written decoders and the generated layout decoder so both interpret
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* the bytes identically.
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*/
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import type { Position } from "unist";
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/** Read a u16 (LE) at `off`. */
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export declare function ru16(view: DataView, off: number): number;
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/** Read a u32 (LE) at `off`. */
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export declare function ru32(view: DataView, off: number): number;
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/** Read a UTF-8 string of `len` bytes at `off`. Very short ASCII runs decode
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* with a charCode loop — TextDecoder's per-call overhead dominates there. The
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* threshold is lower than the encode-side `INLINE_STR_MAX`: decoding builds a
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* JS string by concatenation, which costs more per char than storing bytes.
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* Measured crossover ~8-12 bytes (Node 24: 8B 30 vs 57 ns, 16B 64 vs 57). */
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export declare function rstr(buf: Uint8Array, off: number, len: number): string;
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/**
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* Decode the 24-byte position block ([startOffset, endOffset, startLine,
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* startColumn, endLine, endColumn], u32 LE each) shared by the walk prefixes
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* and the snapshot node structs. A zero start line is the sentinel for
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* synthesized nodes with no source range (e.g. GFM autolink-literal nodes, or a
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* plugin-built replacement spliced by the rebuild): unist lines are 1-based, so
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* line 0 always means "no source position" — even when the rebuild has rebased
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* the (otherwise zero) offset by the spliced subtree's source base. Surfaced as
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* `undefined` so a node reads the same however it's reached.
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*/
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export declare function readPosition(view: DataView, off: number): Position | undefined;
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