Combined from primary sources listed below.
See primary docmentation in context for method isNaN.
method isNaN(Rational:D: --> Bool:D)
Tests whether the invocant's Num value is a NaN, an acronym for Not available Number. That is both its numerator and denominator are zero.
See primary docmentation in context for method isNaN.
method isNaN(Complex:D: --> Bool:D)
Returns true if the real or imaginary part is NaN (not a number).
say (NaN+5i).isNaN; # OUTPUT: «True»
say (7+5i).isNaN; # OUTPUT: «False»