div is the integer division operator. If the floating point is truncated, the result is rounded to the preceding lower integer.
say 10 div 3; # 3 say -10 div 3; # -4
mod is another form of the modulo:
say 10 % 3; # 1 say 10 mod 3; # 1
Unlike the / and % operators, the div and mod forms do not cast the operands to the numeric value. Compare the following two examples.
say 10 % "3"; # 1
With a mod operator, an error occurs:
say 10 mod "3";
Calling 'infix:<mod>' will never work with argument types (Int, Str) Expected any of: :(Real $a, Real $b)
To satisfy the requirements, you may make the type conversion explicitly using either the + prefix operator:
say 10 mod +"3"; # 1
or calling the .Int method:
say 10 mod "3".Int; # 1