System.unique_integer

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unique_integer(modifiers \\ [])

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Specs

unique_integer([:positive | :monotonic]) :: integer()

Generates and returns an integer that is unique in the current runtime instance.

"Unique" means that this function, called with the same list of modifiers, will never return the same integer more than once on the current runtime instance.

If modifiers is [], then a unique integer (that can be positive or negative) is returned. Other modifiers can be passed to change the properties of the returned integer:

  • :positive - the returned integer is guaranteed to be positive.
  • :monotonic - the returned integer is monotonically increasing. This means that, on the same runtime instance (but even on different processes), integers returned using the :monotonic modifier will always be strictly less than integers returned by successive calls with the :monotonic modifier.

All modifiers listed above can be combined; repeated modifiers in modifiers will be ignored.

Inlined by the compiler.