ios - What does << mean in Swift language? -


please explain me strange swift syntax, i've tried google , checked apple's docs haven't find example of using it. here code tutorial i'm trying follow. let fsboundarycategory: uint32 = 1 << 0

i don't meaning of <<.

it's not twice less or :) please, explain, i'm curious :)

this "bit shifting" operator.

maybe apple documentation ( goo.gl/dxvbjd ) complicated start with.

but, basic idea initial bit (1) representation : 00000000000000000000000000000001

if shift 1 bit, using either syntax 0b10 or 1 0x1 << 1 bit goes 1 place left : 00000000000000000000000000000010. can shift 2 place using 0b100 or 0x1 << 2 , on...

here table i've made another question, might : http://goo.gl/7d8egy


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