Rewrite to Java, add Scanner, TokenTypes, and Main class

README.md

@@ -1,2 +1,6 @@
-# CobaltScript
+# Cobalt
-A small programming language designed for general purpose scripting and for learning interpreter design
+Cobalt is a small programming language designed for general purpose and systems level scripting. This project follows very closely to the curriculum from [Crafting Interpreters](http://craftinginterpreters.com/) by Robert Nystrom, and is intended to be a pet project for myself to learn programming language design and interpreter design concepts.
+
+Currently, Cobalt follows the same grammer and design structure as [Lox](https://github.com/munificent/craftinginterpreters), the language featured in Nystrom's book. However, I eventually plan to mutate Cobalt from these design patterns and create a unique syntax and structure once I have reached a high enough proficiency.
+
+This project is a **work in progress**, so some things might be a bit broken. YMMV :)

cobalt/Cobalt.java

@@ -0,0 +1,68 @@
+package cobalt;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.nio.charset.Charset;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.List;
+
+public class Cobalt {
+
+    static boolean hadError = false;
+
+    public static void main(String[] args) throws IOException {
+        if (args.length > 1) {
+            System.out.println("Usage: cobalt [script]");
+            System.exit(64);
+        } else if (args.length == 1) {
+            //runFile(args[0]);
+        } else {
+            //runPrompt()
+        }
+    }
+
+    private static void runFile(String path) throws IOException {
+        byte[] bytes = Files.readAllBytes(Paths.get(path));
+        run(new String(bytes, Charset.defaultCharset()));
+        if (hadError) System.exit(65);
+    }
+
+    private static void runPrompt() throws IOException {
+        InputStreamReader input = new InputStreamReader(System.in);
+        BufferedReader reader = new BufferedReader(input);
+
+        for (;;) {
+            System.out.print("> ");
+            String line = reader.readLine();
+            if (line == null) break;
+            run(line);
+            hadError = false;
+        }
+    }
+
+    private static void run(String source) {
+        // Wont compile since we don't use the standard Java Scanner,
+        // gets implemented further in the textbook
+        Scanner scanner = new Scanner(source);
+        // Same situation for Token type
+        List<Token> tokens = scanner.scanTokens();
+
+        for (Token token : tokens) {
+            System.out.println(token);
+        }
+    }
+
+    static void error(int line, String message) {
+        report(line, "", message);
+    }
+
+    private static void report(int line, String where, String message) {
+        System.err.println(
+            "[line " + line + "] Error" + where + ": " + message
+        );
+        hadError = true;
+
+    }
+}

cobalt/Scanner.java

@@ -0,0 +1,34 @@
+package cobalt;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import static cobalt.TokenType.*;
+
+class Scanner {
+    private final String source;
+    private final List<Token> tokens = new ArrayList<>();
+    private int start = 0;
+    private int current = 0;
+    private int line = 0;
+
+    Scanner(String source) {
+        this.source = source;
+    }
+
+    List<Token> scanTokens() {
+        while (!isAtEnd()) {
+            start = current;
+            scanTokens();
+        }
+
+        tokens.add(new Token(EOF, "", null, line));
+        return tokens;
+    }
+
+    private boolean isAtEnd() {
+        return current >= source.length();
+    }
+}

cobalt/Token.java

@@ -0,0 +1,19 @@
+package cobalt;
+
+class Token {
+    final TokenType type;
+    final String lexeme;
+    final Object literal;
+    final int line;
+
+    Token(TokenType type, String lexeme, Object literal, int line) {
+        this.type = type;
+        this.lexeme = lexeme;
+        this.literal = literal;
+        this.line = line;
+    }
+
+    public String toString() {
+        return type + " " + lexeme + " " + literal;
+    }
+}

cobalt/TokenType.java

@@ -0,0 +1,20 @@
+package cobalt;
+
+enum TokenType {
+    // Single character tokens.
+    LEFT_PAREN, RIGHT_PAREN, LEFT_BRACE, RIGHT_BRACE,
+    COMMA, DOT, MINUS, PLUS, SEMICOLON, SLASH, STAR,
+
+    // One or two character tokens.
+    BANG, BANG_EQUAL, EQUAL, EQUAL_EQUAL,
+    GREATER, GREATER_EQUAL, LESS, LESS_EQUAL,
+
+    // Literals
+    IDENTIFIER, STRING, NUMBER,
+
+    // Keywords
+    AND, CLASS, ELSE, FALSE, FUN, FOR, IF, NIL, OR,
+    PRINT, RETURN, SUPER, THIS, TRUE, VAR, WHILE,
+
+    EOF
+}

include/lexer.h

@@ -1,14 +0,0 @@
-#include <iostream>
-
-#ifndef LEXER_H
-#define LEXER_H
-
-class Lexer
-{
-    private:
-        std::string extension = ".prog";
-    public:
-        Lexer(std::string &file_name);
-};
-
-#endif

include/parser.h

@@ -1,14 +0,0 @@
-#include <iostream>
-
-#ifndef PARSER_H
-#define PARSER_H
-
-class Parser
-{
-    private:
-
-    public:
-        Parser(std::string input_file);
-};
-
-#endif

makefile

@@ -1,20 +0,0 @@
-
-#OBJS specifies which files to compile as part of the project
-OBJS = $(wildcard src/*.cpp) 
-
-#CC specifies which compiler we're using
-CC = g++
-
-#COMPILER_FLAGS specifies the additional compilation options we're using
-# -w suppresses all warnings
-COMPILER_FLAGS = -w
-
-#LINKER_FLAGS specifies the libraries we're linking against
-LINKER_FLAGS = 
-
-#OBJ_NAME specifies the name of our exectuable
-OBJ_NAME = cobalt
-
-#This is the target that compiles our executable
-all : $(OBJS)
-	$(CC) $(OBJS) $(COMPILER_FLAGS) $(LINKER_FLAGS) -o $(OBJ_NAME)

script.prog

@@ -1,3 +0,0 @@
-hello world, this is a lexer test
-hello world
-Kanye's new name is Ye

src/lexer.cpp

@@ -1,30 +0,0 @@
-#include <stdio.h>
-#include <iostream>
-#include <fstream>
-#include "../include/lexer.h"
-
-char c;
-FILE* input_file;
-
-Lexer::Lexer(std::string &file_name) {
-    input_file = fopen(file_name.c_str(),"r");
-    if(input_file == nullptr) {
-        std::cout << "[Error] Script " << input_file << " could not be read\n";
-        exit(1);
-    } 
-
-    c = getc(input_file);
-    if (c == EOF) {
-        //do something related to eof here?
-        fclose(input_file);
-    }
-}
-
-char nextChar() {
-    if (c != EOF) {
-        c = getc(input_file);
-    } else {
-        c = EOF;
-    }
-    return c;
-}

src/main.cpp

@@ -1,15 +0,0 @@
-#include <stdio.h>
-#include <iostream>
-#include <vector>
-
-#include "../include/lexer.h"
-
-int main(int argc, char *argv[]) {
-    if (argc > 1) {
-        std::string file_name(argv[1]);
-        Lexer lex(file_name);
-    } else {
-        std::cout << "[Error] No input file provided\n";
-    }
-    return 0;
-}

src/parser.cpp

@@ -1,8 +0,0 @@
-#include <stdio.h>
-#include <iostream>
-
-#include "../include/parser.h"
-
-Parser::Parser(std::string input_file) {
-
-}