Defining Abstract Syntax Tree

AST is a tree representation of the abstract syntactic structure of the source code of a programming language. The ASTs of programming constructs, such as expressions, flow control statements, and so on, are grouped into operators and operands. ASTs represent relationships between programming constructs, and not the ways they are generated by grammar. ASTs ignore unimportant programming elements such as punctuations and delimiters. ASTs generally contain additional properties of every element in it, which are useful in further compilation phases. Location of source code is one such property, which can be used to throw an error line number if an error is encountered in determining the correctness of the source code in accordance with the grammar (location, line number, column number, and so on, and other related properties are stored in an object of the SourceManager class in Clang frontend for C++).

The AST is used intensively during semantic analysis, where...