Skip to content

README.md

Latest commit

 

History

History
128 lines (88 loc) · 3.03 KB

README.md

File metadata and controls

128 lines (88 loc) · 3.03 KB

TP3 -- Expression Handling and Interpretation with ANTLR

1. What Was Implemented

This practical session focused on integrating arithmetic and boolean expressions within a compiler generated using ANTLR and enabling their interpretation.

Combined Expression Grammar

  • Built a grammar Expr_Calculette capable of parsing:
    • Arithmetic expressions
    • Boolean expressions
  • Allowed programs to contain multiple expressions separated by newline or semicolon.
  • Ensured compatibility between arithmetic and boolean components.

Expression Interpretation

  • Decorated the grammar so that each expression is interpreted during execution.
  • Arithmetic expressions evaluate to numeric values.
  • Boolean expressions evaluate to logical values.
  • Output corresponds to evaluated results.

Comparison Operators

  • Extended boolean expressions to support comparisons between arithmetic expressions.
  • Implemented comparison operators:
    • ==
    • <>
    • <
    • >
    • <=
    • >=
  • Comparison results produce boolean values usable inside logical expressions.

Display Instruction

  • Added instruction:

    Afficher(expr)

  • Allows explicit output of evaluated expressions.

  • Supports both arithmetic and boolean expressions.

  • Interpretation prints evaluation results when invoked.

2. What Was Learned

Expression Integration

  • Combining arithmetic and boolean grammars.
  • Handling expressions of different semantic types.
  • Managing precedence across arithmetic and logical operators.

Grammar Decoration for Interpretation

  • Evaluating expressions directly from grammar rules.
  • Propagating semantic values through attributes.
  • Integrating syntax parsing with runtime evaluation.

Comparison Semantics

  • Converting arithmetic comparisons into boolean expressions.
  • Supporting comparisons inside logical operations.

Language Feature Extension

  • Incrementally extending grammars with new instructions.
  • Adding output instructions similar to programming languages.

Interpreter Construction

  • Using ANTLR grammars to construct interpreters.
  • Executing expression programs directly via parsing.

3. How to Run the Project

  1. Install ANTLR4 and ensure antlr4 and grun are available in the terminal.

  2. Generate lexer and parser files:

    antlr4 Expr_Calculette-ex1.g4
antlr4 Expr_Calculette-ex2.g4
antlr4 Expr_Calculette-ex3.g4
antlr4 Expr_Calculette-ex4.g4

  3. Compile generated Java files:

    javac *.java

  4. Run tests using:

    grun Expr_Calculette start -gui

4. Project Structure

.
├── Expr_Calculette-ex1.g4
├── Expr_Calculette-ex2.g4
├── Expr_Calculette-ex3.g4
├── Expr_Calculette-ex4.g4
├── *.java          # Generated ANTLR files
├── *.class         # Compiled Java files
└── README.md

This TP demonstrated how grammars evolve from parsing expressions to building interpreters capable of evaluating mixed arithmetic and boolean programs.