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Language documentation: Operators §

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(Operators) infix < §

multi sub infix:«<»(Int:D, Int:D)
multi sub infix:«<»(Num:D, Num:D)
multi sub infix:«<»(Real:D, Real:D)

Numeric less than operator.

Coerces both arguments to Real (if necessary); returns True if the first argument is smaller than the second.