The doubling also helps it stand out better in code, in part because it forces you to put space around the :: so that it's not confused with a package name separator.
Aha! Another sneaky instance of required whitespace! (What will this do to golf scores?)

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re^5: Pugs Tic Tac by QM
in thread Pugs Tic Tac by mkirank

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