lpack Reference

Module defined in lua/common/lpack.lua. Fast Lua de/serializer supporting three formats: packed text, binary (using string.buffer), and Lua source. Handles tables, numbers, strings, booleans, vec3, and quat.

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Exports

Functions

M.encode(v)

Encodes a Lua value into a compact packed text format.

• Parameters:
  • v - any - Value to encode (table, number, string, boolean, vec3, quat)
• Returns: string - Packed encoding (starts with 'a')

M.decode(is)

Decodes a packed or binary-encoded string back to a Lua value. Auto-detects format.

• Parameters:
• Returns: table - Parsed result
• Returns: any - Decoded Lua value

M.encodeBin(v)

Encodes a Lua value into binary format using string.buffer.

• Parameters:
  • v - any - Value to encode
• Returns: string - Binary encoding (starts with 'b')

M.encodeBinWorkBuffer(v)

Like encodeBin but returns the work buffer directly (avoids a string copy).

• Parameters:
  • v - any - Value to encode
• Returns: buffer - String buffer object

M.encodeLua(v)

Encodes a Lua value as valid Lua source code that can be loadstring'd.

• Parameters:
  • v - any - Value to encode
• Returns: string - Lua source string

M.decodeLua(s)

Decodes a Lua source string by executing it.

• Parameters:
  • s - string|nil - Lua source (from encodeLua)
• Returns: any - Decoded value

M.encodeDoubleArray(tbl)

Encodes a Lua number array as raw binary double array via FFI.

• Parameters:
  • tbl - table - Array of numbers
• Returns: string - Raw binary data (8 bytes per number)

M.decodeDoubleArray(sda, tbl)

Decodes a raw binary double array back to a Lua table.

• Parameters:
  • sda - string - Binary data from encodeDoubleArray
  • tbl - table|nil - Optional table to populate
• Returns: table - Array of numbers

Internal Notes

• Three encoding formats: packed text ('a' prefix), binary ('b' prefix), and Lua source
• decode() auto-detects format by checking the first byte
• Packed format uses dispatch tables keyed by character codes for fast encoding/decoding
• Binary format leverages LuaJIT string.buffer encode/decode for native type serialization
• Temporarily stops GC during decode for performance
• Type markers in packed format: - (positive number), = (negative number), [ (array), { (dict), | (true), ~ (false), ^ (vec3), & (quat), A-J (strings by length digits)