Perl 6 Deep Dive

Operators for addition and subtraction

The + and - operators are operators for addition and subtraction. The operands must be of the numeric type.

There is not much to say about the operators; their behavior is self-explanatory, as follows:

my $a = 10;say $a + 3;  # 13my $b = 20;say $b - $a; # 10;

In combination with, for example, * and /, the + and - operators have lower precedence, thus the standard arithmetical rules apply.

When it is possible to cast the string to a number (either integer or floating-point), that conversion will be performed by the compiler, and the + and - operators will work with two numeric operands. Consider the following example:

my $str = "42";say $str - 2; # 40

As the operators expect their arguments to be numeric, ...