Grammar for a Programming Language

Syntax and Semantics

The syntax of a programming language defines the rules for constructing valid programs. It specifies the structure and format of the language's expressions, statements, and program units such as functions and classes. A programming language's syntax is usually defined using a formal grammar, such as Backus-Naur form (BNF), which is a notation for describing the syntax of a language.

On the other hand, the semantics of a programming language describe the meaning of the language's constructs. It specifies the behavior of the language's expressions, statements, and program units when executed. For example, the semantics of an assignment statement in a programming language specifies that it assigns a value to a variable.

Structured Programming

Structured programming is a programming paradigm that emphasizes the use of structured programming constructs such as loops, conditionals, and functions to improve the clarity, maintainability, and reliability of software. It was developed in the late 1960s as a response to the perceived problems of unstructured programming, which often led to spaghetti code and difficult-to-maintain software.

A structured programming language is a programming language that supports structured programming constructs. Examples of structured programming languages include C, Pascal, and Ada.

Library

A library is a collection of prewritten code that can be used by software developers to perform common tasks. Libraries often encapsulate complex functionality into easy-to-use functions or classes, which can save developers time and effort.

A programming language's standard library is a collection of libraries that are included with the language itself. It provides a set of common functionality that can be used by all programs written in that language. For example, the C++ standard library provides functions for input/output, string manipulation, and mathematical operations.