Programming Environment Concepts

Environment

• In programming, an environment refers to the context in which a program or script is executed.
• It includes the variables, functions, and objects that are available for use.
• Environments can be thought of as a container that holds the state of the program.

Types of Environments

• Global Environment: The top-level environment that contains all the built-in variables, functions, and objects.
• Local Environment: A temporary environment created when a function or block is executed, which contains its own local variables and objects.
• Module Environment: An environment created when a module is imported, which contains the variables, functions, and objects defined in the module.

Types

• Primitive Types: Basic types that are built into the programming language, such as:
  • Integers (e.g. int in Python)
  • Floating-point numbers (e.g. float in Python)
  • Strings (e.g. str in Python)
  • Booleans (e.g. bool in Python)
• Complex Types: Types that are composed of primitive types, such as:
  • Lists (e.g. list in Python)
  • Tuples (e.g. tuple in Python)
  • Dictionaries (e.g. dict in Python)
  • Objects (e.g. object in Python)
• User-Defined Types: Types created by the programmer, such as:
  • Classes (e.g. class in Python)
  • Structures (e.g. struct in C)

Type Systems

• Static Type System: A type system that checks the types of variables at compile-time, such as in C or Java.
• Dynamic Type System: A type system that checks the types of variables at runtime, such as in Python or JavaScript.
• Weak Type System: A type system that allows implicit type conversions, such as in JavaScript.
• Strong Type System: A type system that does not allow implicit type conversions, such as in Python.

Environment

• A program's environment includes variables, functions, and objects available for use, serving as a container for the program's state.

Types of Environments

• Global Environment: the top-level environment containing all built-in variables, functions, and objects.
• Local Environment: a temporary environment created when a function or block is executed, containing local variables and objects.
• Module Environment: an environment created when a module is imported, containing variables, functions, and objects defined in the module.

Data Types

Primitive Types

• Basic types built into the programming language, including:
  • Integers (e.g. int in Python)
  • Floating-point numbers (e.g. float in Python)
  • Strings (e.g. str in Python)
  • Booleans (e.g. bool in Python)

Complex Types

• Types composed of primitive types, including:
  • Lists (e.g. list in Python)
  • Tuples (e.g. tuple in Python)
  • Dictionaries (e.g. dict in Python)
  • Objects (e.g. object in Python)

User-Defined Types

• Types created by the programmer, including:
  • Classes (e.g. class in Python)
  • Structures (e.g. struct in C)

Type Systems

• Static Type System: checks types at compile-time (e.g. C or Java).
• Dynamic Type System: checks types at runtime (e.g. Python or JavaScript).
• Weak Type System: allows implicit type conversions (e.g. JavaScript).
• Strong Type System: does not allow implicit type conversions (e.g. Python).