Expressions Foundation

An expression is also used in a program to determine a value. Expressions can only be evaluated at runtime of a program and they always return a value. Simple expressions reference only one single program element, such as a variable, a literal or a function call. Examples for simple expressions are:

? "Hundred"      // output of a character value     : Hundred 
? 100            // output of a numeric value       : 100 
? Sqrt(4)        // output of a function value      : 2 
? Date()         // output of a date                : 12/06/94 

Nested or complex expressions including a combination of several language elements along with operators can be created. This is shown in the following examples of assignments:

nNumber := 10                    // Simple literal 
nResult := nNumber + 90          // Variable plus literal 
nResult := nResult / (nNumber-5) // Variable divided by expression 

The operators that can be used in a complex expression depend on the data type of the variables, literals or function values.