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  • April Martin thinks this is interesting:

a​c​t​i​o​n​:​ ​"​m​a​p​T​y​p​e​C​h​a​n​g​e​d​:​"​,

From

Cover of iOS Programming: The Big Nerd Ranch Guide

Note

This is incorrect. Should be:

segmentedControl.addTarget(self, action: #selector(MapViewController.mapTypeChanged(_:)), forControlEvents: .ValueChanged)