Operators

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Mathematical Operators

The following mathematical operators are used in KoLmafia:

+ AdditionPerforms addition and string concatenation
- SubtractionPerforms subtraction
* MultiplicationPerforms multiplication
/ DivisionPerforms division
 % ModuloReturns the remainder after division

Note that, with the exception of using "+" for string concatenation, these operators can only be used on int or float datatypes.

Relational Operators

To follow these examples, a basic understanding of the concepts found on Control Structures would be helpful.

In order to create more complex if statements, we need to understand the basic relational operators:

== equal to
 != not equal to
< less than
> greater than
<= less than or equal to
>= greater than or equal to

Note that you cannot mix datatypes within a comparison or KoLmafia will abort wil an error, with the exception of mixing types int and float, where KoLmafia will do a transparent type conversion behind-the-scenes. If you need to compare different datatypes, use one or more of the Datatype Conversion functions.


if ( true == true )
{
   print( "This line DOES get printed." );
}
if ( true == false )
{
   print( "This line does NOT get printed." );
}
if ( 1 == 1.0 )
{
   print( "This line DOES get printed." );
}
if ( 1 == 2 )
{
   print( "This line does NOT get printed." );
}



Boolean Operators

&& and
|| or
 ! not

Note that the above operators only work with boolean values & datatypes. To make use of them with other datatypes, you will either need to first perform a Datatype Conversion, or you will need to nest your operations such that a boolean value is used with the boolean operators.


if ( true && true )
{
   print( "This line DOES get printed (both possibilities proved true)." );
}
if ( true && false )
{
   print( "This line does NOT get printed (only one possibility proved true)." );
}
if ( true || false )
{
   print( "This line DOES get printed (since at least one of the possibilities proved true)." );
}
if ( ! false )
{
   print( "This line DOES get printed (since the not operator converted false to true)." );
}

We also need to understand operator precedence. Statements inside a () pair are always evaluated first, then from left to right.

if ( true || true && false )
{
   print( "This line DOES get printed." );
	 // evaluated left-to-right
	 // true or (true && false) returns true
}
if ( true && ( true && false ) )
{
   print( "This line does NOT get printed." );
	 // ( true && false ) is evaluated first since it is inside of parentheses
	 // so we end up evaluating ( true && false ) which returns false
}
if ( true && ! ( true && false ) )
{
   print( "This line DOES get printed." );
	 // ( true && false ) is evaluated first since it is inside of parentheses
	 // the ! operator converts the false from ( true && false ) to true
	 // ( true && true ) returns true
}