GEPA.Strategies.CandidateSelector behaviour (GEPA v0.3.0)

Behavior for selecting which program candidate to mutate.

Candidate selection strategies balance exploration and exploitation in the optimization search space.

Summary

Callbacks

Select a candidate program index for mutation.

Callbacks

select(term, t, arg3)

@callback select(term(), GEPA.State.t(), :rand.state() | nil) ::
  {GEPA.Types.program_idx(), :rand.state()}
  | {GEPA.Types.program_idx(), term(), :rand.state()}

Select a candidate program index for mutation.

Parameters

selector_state: Struct or module implementing the selection logic
state: Current optimization state
rand_state: Erlang random state (optional, for stochastic selectors)

Returns

Stateless selectors: {program_idx, new_rand_state} Stateful selectors: {program_idx, updated_selector, new_rand_state}