Abstract Syntax Trees

Saturday, March 18th 2023

An Abstract Syntax Tree (AST) is a data structure commonly used in computer science to represent the syntax of a program or a piece of code in a way that is both more compact and easier to process than the original source code.

An AST is essentially a tree-like representation of the structure of the code, with each node in the tree representing a different part of the code. Each node in the tree represents a syntactic construct of the programming language, such as an expression, a statement, a function, a variable declaration, or a control structure like if-else or loops. The nodes can have child nodes representing the sub-expressions or sub-statements that make up the larger construct.

The AST is created during the process of parsing the source code, which involves breaking the code down into a series of tokens or individual pieces of code that can be analyzed and understood by the computer. Once the code has been parsed, the AST is constructed by building up a tree structure that represents the syntactic relationships between the tokens.

The AST is used by various tools in the compilation and interpretation process, such as compilers, interpreters, and code analysis tools. The AST makes it easier to analyze and manipulate the code because it provides a structured and abstract representation of the code that is independent of the particular syntax of the programming language.

Overall, the AST is an important concept in computer science and plays a key role in many areas of software development, from code optimization to static analysis and code refactoring.