Perl 6 Deep Dive

Numeric data type

The Num type is used to store floating-point values. It corresponds to the double precision in C.

Notice that, in Perl 6, the Num value is only created when the numeric literal is spelled in a scientific notation. That is, the E part of the value must be present.

Thus, in the following examples, the numbers with only a decimal point will be of the Rat type:

say 3.14;    # Ratsay 123.456; # Ratsay 0.9;     # Rat

The following numbers represent the same values, but are of the Num type, as they use the exponential part in their definition:

say 3.14E0;    # Numsay 1.23456E2; # Numsay 9E-1;      # Num

Remember that the Num values use the packed IEEE binary format, so they are limited in precision, while Rat numbers keep their numerator and ...