Built-in Reducer: Append — reducer

A functional reducer that appends new elements to an existing vector or list. This is the standard pattern for accumulating results or logs across multiple agent steps.

Usage

reducer_append(current, new)

Arguments

current: The current value in the state.
new: The new value to be added.

Value

A combined vector or list containing both current and new.

Examples

if (FALSE) { # \dontrun{
# Accumulate a trace of agent IDs
state <- AgentState$new(
  initial_data = list(visited = character()),
  reducers = list(visited = reducer_append)
)

state$update(list(visited = "agent_a"))
state$update(list(visited = "agent_b"))

print(state$get("visited")) # [1] "agent_a" "agent_b"
} # }