StreamLogHandler

StreamLogHandler is a simple implementation of LogHandler for directing Logger output to either stderr or stdout via the factory methods.

Logging.swift:1310
struct StreamLogHandler

Metadata is merged in the following order:

  1. Metadata set on the log handler itself is used as the base metadata.

  2. The handler’s metadataProvider is invoked, overriding any existing keys.

  3. The per-log-statement metadata is merged, overriding any previously set keys.