An expression is a mathematical, logical, or string formula, consisting of the corresponding operations to calculate the value. Mathematical and logical expression can appear to the right of the equal sign in the assignment statements, and to be a parameter of procedures or functions. A logical expression can also be a condition in the If, While, and For control structures. Expressions consist of constants, variables, and functions joined by symbols of logical and/or arithmetic operations.
- 4.5. Language expressions