special characters - What is the purpose of double colons in Lua? -

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i have been aware version 5.3 lua had come out not long ago hadn't had reason visit documentation online until now. may wrong, not believe remember usage of double-colons :: used abundantly there.

i see considered "special token" others (greater than, less than, asterisks, etc) know for.

what purpose of using them in lua?

:: used 1 thing in lua *:

declaring labels jumping goto.

goto label ::label::

the goto statement transfers program control label. syntactical reasons, labels in lua considered statements too:

stat ::= goto name stat ::= label label ::= ‘::’ name ‘::’

a label visible in entire block defined, except inside nested blocks label same name defined , inside nested functions. goto may jump visible label long not enter scope of local variable.

labels , empty statements called void statements, perform no actions.

* don't consider extensive use extended bnf in documentation use in lua itself.


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