Various programming languages provide simplicity and ease in software development by supporting dynamic data typing of functions and variables (also referred to as, “dynamic typing”). Generally, programming languages that support dynamic typing may permit source code to use a variable without need for prior declaration of a variable data type (e.g., integer, Boolean, string, etc.), and may permit declaration of a function without need for prior declaration of a data type for a function return value or for a function parameter. Examples of programming languages that support dynamic data typing include such scripting languages as PHP, Perl, and JavaScript, which are often used in client-server environments to implement server-side programs, client-side programs, or both.
In contrast to dynamic data typing, programming languages that support static data typing (also referred to as, “static typing”) may require source code to declare the data type of variables, function return values, and function parameters, either prior to or at the time of their use. Unlike dynamic typing, static typing causes data type verification (also known as type safety) of variables and functions to occur before runtime (e.g., during coding or compilation using a type checker), thereby allowing for data type errors to be detected much earlier in the development process. Additionally, source code that uses static typing often is easier to refactor (e.g., for better code readability, reduced code complexity, or easier code maintainability) than source code that uses dynamic typing.