state_child.md

OpenSpiel state methods: child

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child(action: int)

Returns a new state that results from applying the specified action to a clone of the current state. The original state is not modified. This is equivalent to cloning the state and then calling apply_action() on the clone.

Examples:

import pyspiel

game = pyspiel.load_game("tic_tac_toe")
state = game.new_initial_state()

# Create a child state by taking the center square
child_state = state.child(4)
print(child_state)
# The original state is unchanged
print(state.history())       # Output: []
print(child_state.history()) # Output: [4]