# mathlibdocumentation

topology.instances.discrete

# Instances related to the discrete topology #

We prove that the discrete topology is a first-countable topology, and is second-countable for an encodable type. Also, in linear orders which are also pred_order and succ_order, the discrete topology is the order topology.

When importing this file and data.nat.succ_pred, the instances second_countable_topology ℕ and order_topology ℕ become available.

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