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sub snapper($sleep = 0.1, :$stop, :$reset --> Nil)

The snapper routine starts a separate thread that will call snap repeatedly until the end of program. It is exported by default.

By default, it will call snap every 0.1 second. The only positional parameter is taken to be the delay between snaps.

Please see the snapper module for externally starting a snapper without having to change the code. Simply adding -Msnapper as a command line parameter, will then start a snapper for you.