Flatbuf.Schema.Union (flatbuf v0.1.0)

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A FlatBuffers union declaration.

variants is a list of {atom_name, type_spec, discriminator_int} triples in declaration order. Discriminator 0 is reserved for NONE (the absent state); variants get 1, 2, … starting from the first declared, unless the schema assigns explicit values (A = 555).

underlying_type is the integral scalar that carries the discriminator on the wire (union U : int { … }, since upstream v23.5.8). It defaults to the historical :u8; an explicit underlying type widens both the table's type field and the element size of a vector-of-union's types vector. A signed underlying type permits negative discriminator values.

Variant type_spec is one of {:table, fqn}, {:struct, fqn} (since upstream v1.12), or :string (also since v1.12).

Summary

Types

t()
underlying()
variant()

Types

t()

@type t() :: %Flatbuf.Schema.Union{
  attributes: map(),
  docs: [String.t()],
  name: String.t(),
  namespace: String.t() | nil,
  short_name: String.t(),
  underlying_type: underlying(),
  variants: [variant()]
}

underlying()

@type underlying() :: :i8 | :u8 | :i16 | :u16 | :i32 | :u32 | :i64 | :u64

variant()

@type variant() :: {atom(), Flatbuf.Schema.type_spec(), integer()}