COMP 430: Language Design and Compilers

Language Name: J2C

Goal

Implement a compiler for the designed language, complete with:

A parser

A typechecker / static semantic analyzer

A code generator

Author

Ibtehaz Utsay

Documentation

Link to Initial Proposal: https://docs.google.com/document/d/1mQWRqwIdn_nY9M3pWh7nB8k_Ht-t0xxur-jjfsBvdB4/edit

Link to Final Documentation: https://docs.google.com/document/d/1obbLbR7vw4AfNE7bBT4wHFp_kHFFeNJ8NmIOaTUIuzI/edit

Target Language: C

Abstract Syntax:

var is a variable classname is the name of a class methodname is the name of a method str is a string i is an integer

Original Grammer (Left-recursive, no operator precedence)

type:: = int | bool | void | Built-in types
    classname; includes Object and String
op:: = * | / | + | - | % | < | > | == | != Arithmetic operations
exp:: = var | str | i | Variables, strings, and integers are expressions
this | Refers to my instance
exp op exp | Arithmetic operations
new classname(exp*) | Creates a new instance of a class
exp. methodname(exp*) | Calls a method
(type)exp | Casts an expression as a type/Runtime exception for improper casting
vardec:: = type var | Variable declaration
stmt:: = vardec = exp; | Variable declaration
var = exp; | Assignment
while (exp) stmt | while loops
break; | break
{ stmt* } | block
if (exp) stmt else stmt | if/else
return exp; | return an expression
return; | return Void
println(exp) | Prints something to the terminal
exp. methodname(exp*) | Calls a method
access ::= public | private | protected
methoddef ::= access type methodname(vardec*) stmt vardecs are comma-separated 
instancedec ::= access vardec; instance variable declaration classdef ::= class classname extends classname {
instancedec* 
constructor(vardec*) stmt vardecs are comma-separated 
methoddef*
} 
program ::= classdef* exp exp is the entry point

New Grammar (Not left-recursive and handles operator precedence)

var is a variable
classname is the name of a class
methodname is the name of a method
str is a string
i is an integer
type:: = int | bool | str | classname
primary_exp ::= var | str | int | true | false
multiplicative_op ::= * | /
multiplicative_exp ::= primary_exp(multiplicative_op primary_exp)*
additive_op ::= + | /
additive_exp ::= multiplicative_exp (additive_op multiplicative_exp)*
comparison_op ::= < | > | == | !=
comparsion_exp ::= additive_exp | additive_exp comparison_op additive_exp
exp ::= var.methodname(exp*) | new classname(exp*) | comparison_exp
new classname(exp*) | Creates a new instance of a class
exp. methodname(exp*) | Calls a method
(type)exp | Casts an expression as a type/Runtime exception for improper casting
vardec:: = type var | Variable declaration
stmt:: = vardec = exp; | Variable declaration
var = exp; | Assignment
while (exp) stmt | while loops
break; | break
{ stmt* } | block
if (exp) stmt else stmt | if/else
return exp; | return an expression
return; | return Void
println(exp) | Prints something to the terminal
exp. methodname(exp*) | Calls a method
access ::= public | private | protected
methoddef ::= access type methodname(vardec*) stmt vardecs are comma-separated 
instancedec ::= access vardec; instance variable declaration classdef ::= class classname extends classname {
instancedec* 
constructor(vardec*) stmt vardecs are comma-separated 
methoddef*

Features

Computation Abstraction Non-Trivial Feature: Class based inheritance + Methods

Non-Trivial Feature #2: Subtyping

Non-Trivial Feature #3: Method Overloading

Work Planned for Custom Component: Access Modifiers

Testing

To run the tests:

mvn compile
mvn test

To view reports:

mvn jacoco: report
open target/site/jacoco/index.html