Raxol.AgentClientProtocol.Schema.MaybeUndefined (Raxol Agent Client Protocol v0.1.0)

Copy Markdown View Source

A three-state value type: :undefined, nil (null), or {:value, term}.

Distinguishes a missing field (undefined) from an explicitly null field. This is load-bearing for partial-update semantics where omitting a field means "don't change" and setting it to null means "clear".

Raxol.AgentClientProtocol.Schema.Unstable.SessionInfoUpdate uses this type: its decoder maps an absent key to :undefined and passes a present value through from_json/1 (null -> nil, anything else -> {:value, v}); its encoder omits :undefined fields via the {:skip} sentinel returned by to_json/1.

JSON serialization

  • :undefined -> field is omitted from JSON output
  • nil -> null
  • {:value, x} -> the JSON encoding of x

Ported from the MIT f1729/agent_client_protocol (c) 2025 f1729; see NOTICE.md.

Summary

Types

t(value)

Functions

from_json(v)

Decodes from JSON deserialization. Call with :missing if the key was not present, or with the raw value if it was.

map_value(arg1, fun)

Maps a function over the value, preserving undefined/null.

null?(arg1)

Returns true if the value is null.

to_json(arg1)

Encodes for JSON serialization. Returns {:skip} for undefined (the caller omits the field), nil for null, or the value itself.

undefined?(arg1)

Returns true if the value is undefined.

update_to(arg1, current)

Applies partial-update semantics against a current value.

value(arg1)

Returns the inner value, or nil if undefined or null.

value?(arg1)

Returns true if the value carries a value.

Types

t(value)

@type t(value) :: :undefined | nil | {:value, value}

Functions

from_json(v)

@spec from_json(:missing | term()) :: t(term())

Decodes from JSON deserialization. Call with :missing if the key was not present, or with the raw value if it was.

map_value(arg1, fun)

@spec map_value(t(value), (value -> mapped)) :: t(mapped)
when value: term(), mapped: term()

Maps a function over the value, preserving undefined/null.

null?(arg1)

@spec null?(t(term())) :: boolean()

Returns true if the value is null.

to_json(arg1)

@spec to_json(t(term())) :: {:skip} | nil | term()

Encodes for JSON serialization. Returns {:skip} for undefined (the caller omits the field), nil for null, or the value itself.

undefined?(arg1)

@spec undefined?(t(term())) :: boolean()

Returns true if the value is undefined.

update_to(arg1, current)

@spec update_to(t(value), value | nil) :: value | nil when value: term()

Applies partial-update semantics against a current value.

  • :undefined -> returns the current value unchanged (don't change)
  • nil -> returns nil (clear)
  • {:value, v} -> returns v (set)

value(arg1)

@spec value(t(value)) :: value | nil when value: term()

Returns the inner value, or nil if undefined or null.

value?(arg1)

@spec value?(t(term())) :: boolean()

Returns true if the value carries a value.