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    Operators precedence
    
    

    
    

    
    

    
    
    
    

    



    

        Operators precedence

        Composed mathematical expressions, such as 1 + 3 / 4 - 9 can be evaluated in many ways, depending on which operator: +, / or - is applied first.

            While humans can make decisions based on common sense, Prompto has a pre-defined set of rules to ensure the sequence is always the same.

            This is called operator precedence. In Prompto, the mathematical operator precedence is as follows:
            

                - exp -> minus
                not exp -> logical not
                exp * exp -> multiply
                exp / exp -> divide
                exp % exp -> remainder
                exp \ exp -> integer divide
                exp + exp -> add
                exp - exp -> subtract
                exp < exp -> less than
                exp <= exp -> less than or equal
                exp > exp -> greater than
                exp >= exp -> greater than or equal
                exp = exp -> equal
                exp ~ exp -> roughly equal
                exp or exp -> logical or
                exp and exp -> logical and
            
        This means that in the above expression, the evaluation is performed in the following sequence:
        3 / 4, then 1 + 0.75 and finally 1.75 - 9.
        
        Although Prompto precedence is similar to most programming languages, the above list can be hard to remember.

            Precedence can become even more complex with Prompto, because it uses a number of keywords as operators,
            such as in, contains, as and others.

            The best way to keep code unambiguous and avoid mistakes is to use parenthesis.
        

        Parenthesis expressions

        A parenthesis expression is used to manage precedence.

            A parenthesis expression is a code fragment which produces a value, whose type is determined by the enclosed value, and which can then be used as an input for other operations: print, write, method call and so forth.

            A parenthesis expression has the form ( exp ).

        
        
            
        
        As you can see, both expressions trigger the same result. But using parenthesis makes it clear for readers what the intent is.