Welcome to the section on syntax analysis! Syntax analysis, also known as parsing, is the process of analyzing a sequence of tokens to determine their grammatical structure according to the rules of a formal grammar. In the context of programming languages, syntax analysis is the first step in the compilation process.

What is Syntax Analysis?

Syntax analysis is the process of determining the syntactic structure of a sequence of tokens. It checks whether the sequence of tokens conforms to the grammar rules of a programming language. If the sequence is syntactically correct, it is considered well-formed.

Key Concepts

  • Tokens: The smallest units of a programming language, such as keywords, identifiers, literals, and operators.
  • Grammar: A set of rules that defines the structure of a programming language.
  • Parse Tree: A tree representation of the syntactic structure of a sequence of tokens.

Syntax Analysis Process

The syntax analysis process typically involves the following steps:

  1. Tokenization: The input program is divided into a sequence of tokens.
  2. Parsing: The sequence of tokens is analyzed to determine its syntactic structure.
  3. Error Reporting: If the sequence of tokens does not conform to the grammar rules, errors are reported.

Example

Let's take a look at an example in Python:

def add(a, b):
    return a + b

In this example, the syntax analysis process would break down the code into tokens and then construct a parse tree.

Tokenization

['def', 'add', '(', 'a', ',', 'b', ')', ':', 'return', 'a', '+', 'b', ';']

Parse Tree

<FunctionDef>
    <name>add</name>
    <args>
        <arguments>
            <arg>a</arg>
            <arg>b</arg>
        </arguments>
    </args>
    <body>
        <Return>
            <expr>
                <BinaryOp>
                    <left>
                        <Name>a</Name>
                    </left>
                    <op>+</op>
                    <right>
                        <Name>b</Name>
                    </right>
                </BinaryOp>
            </expr>
        </Return>
    </body>
</FunctionDef>

Resources

For further reading on syntax analysis, you can visit our Parsing Techniques page.