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Ilja
2025-10-03 18:11:35 +02:00
commit da33be9b02
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39
.gitignore vendored Normal file
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target/
!.mvn/wrapper/maven-wrapper.jar
!**/src/main/**/target/
!**/src/test/**/target/
.kotlin
### IntelliJ IDEA ###
.idea/modules.xml
.idea/jarRepositories.xml
.idea/compiler.xml
.idea/libraries/
*.iws
*.iml
*.ipr
### Eclipse ###
.apt_generated
.classpath
.factorypath
.project
.settings
.springBeans
.sts4-cache
### NetBeans ###
/nbproject/private/
/nbbuild/
/dist/
/nbdist/
/.nb-gradle/
build/
!**/src/main/**/build/
!**/src/test/**/build/
### VS Code ###
.vscode/
### Mac OS ###
.DS_Store

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.idea/.gitignore generated vendored Normal file
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# Default ignored files
/shelf/
/workspace.xml

7
.idea/encodings.xml generated Normal file
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<?xml version="1.0" encoding="UTF-8"?>
<project version="4">
<component name="Encoding">
<file url="file://$PROJECT_DIR$/src/main/java" charset="UTF-8" />
<file url="file://$PROJECT_DIR$/src/main/resources" charset="UTF-8" />
</component>
</project>

14
.idea/misc.xml generated Normal file
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<?xml version="1.0" encoding="UTF-8"?>
<project version="4">
<component name="ExternalStorageConfigurationManager" enabled="true" />
<component name="MavenProjectsManager">
<option name="originalFiles">
<list>
<option value="$PROJECT_DIR$/pom.xml" />
</list>
</option>
</component>
<component name="ProjectRootManager" version="2" project-jdk-name="openjdk-25" project-jdk-type="JavaSDK">
<output url="file://$PROJECT_DIR$/out" />
</component>
</project>

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pom.xml Normal file
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<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.craftinginterpreters.lox</groupId>
<artifactId>jlox</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>25</maven.compiler.source>
<maven.compiler.target>25</maven.compiler.target>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.4.1</version>
<configuration>
<archive>
<manifest>
<mainClass>com.craftinginterpreters.lox.Lox</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>
</project>

66
src/main/java/com/craftinginterpreters/lox/Lox.java Normal file
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package com.craftinginterpreters.lox;
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;
//TIP To <b>Run</b> code, press <shortcut actionId="Run"/> or
// click the <icon src="AllIcons.Actions.Execute"/> icon in the gutter.
public class Lox {
private static boolean hadError = false;
static void main(String[] args) throws IOException {
if (args.length > 1){
System.exit(64);
}
if (args.length == 1){ // Filepath
runFile(args[0]);
}
else{
runPrompt();
}
}
private static void runFile(String filePath) throws IOException {
byte[] bytes = Files.readAllBytes(Paths.get(filePath));
run(new String(bytes, Charset.defaultCharset()));
if(hadError) System.exit(65);
}
private static void runPrompt() throws IOException {
InputStreamReader stream = new InputStreamReader(System.in);
BufferedReader reader = new BufferedReader(stream);
while(true){
System.out.print("> ");
String line = reader.readLine();
if(line == null) break;
run(line);
hadError = false;
}
}
private static void run(String source){
Scanner scanner = new Scanner(source);
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;
}
}

202
src/main/java/com/craftinginterpreters/lox/Scanner.java Normal file
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package com.craftinginterpreters.lox;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import static com.craftinginterpreters.lox.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;
private static final Map<String, TokenType> keywords;
static {
keywords = new HashMap<>();
keywords.put("and", AND);
keywords.put("class", CLASS);
keywords.put("else", ELSE);
keywords.put("false", FALSE);
keywords.put("for", FOR);
keywords.put("fun", FUN);
keywords.put("if", IF);
keywords.put("nil", NIL);
keywords.put("or", OR);
keywords.put("print", PRINT);
keywords.put("return", RETURN);
keywords.put("super", SUPER);
keywords.put("this", THIS);
keywords.put("true", TRUE);
keywords.put("var", VAR);
keywords.put("while", WHILE);
}
Scanner(String source) {
this.source = source;
}
List<Token> scanTokens() {
while (!isAtEnd()) {
// We are at the beginning of the next lexeme.
start = current;
scanToken();
}
tokens.add(new Token(EOF, "", null, line));
return tokens;
}
private boolean isAtEnd() {
return current >= source.length();
}
private void scanToken() {
char c = advance();
switch (c) {
case '(': addToken(LEFT_PAREN); break;
case ')': addToken(RIGHT_PAREN); break;
case '{': addToken(LEFT_BRACE); break;
case '}': addToken(RIGHT_BRACE); break;
case ',': addToken(COMMA); break;
case '.': addToken(DOT); break;
case '-': addToken(MINUS); break;
case '+': addToken(PLUS); break;
case ';': addToken(SEMICOLON); break;
case '*': addToken(STAR); break;
case '!':
addToken(match('=') ? BANG_EQUAL : BANG);
break;
case '=':
addToken(match('=') ? EQUAL_EQUAL : EQUAL);
break;
case '<':
addToken(match('=') ? LESS_EQUAL : LESS);
break;
case '>':
addToken(match('=') ? GREATER_EQUAL : GREATER);
break;
case '/':
if (match('/')) {
// A comment goes until the end of the line.
while (peek() != '\n' && !isAtEnd()) advance();
} else {
addToken(SLASH);
}
break;
case ' ':
case '\r':
case '\t':
// Ignore whitespace.
break;
case '\n':
line++;
break;
case '"': string(); break;
default:
if (isDigit(c)) {
number();
} else if (isAlpha(c)) {
identifier();
} else {
Lox.error(line, "Unexpected character.");
}
Lox.error(line, "Unexpected character.");
break;
}
}
private void identifier() {
while (isAlphaNumeric(peek())) advance();
String text = source.substring(start, current);
TokenType type = keywords.get(text);
if (type == null) type = IDENTIFIER;
addToken(type);
}
private void number() {
while (isDigit(peek())) advance();
// Look for a fractional part.
if (peek() == '.' && isDigit(peekNext())) {
// Consume the "."
advance();
while (isDigit(peek())) advance();
}
addToken(NUMBER,
Double.parseDouble(source.substring(start, current)));
}
private void string() {
while (peek() != '"' && !isAtEnd()) {
if (peek() == '\n') line++;
advance();
}
if (isAtEnd()) {
Lox.error(line, "Unterminated string.");
return;
}
// The closing ".
advance();
// Trim the surrounding quotes.
String value = source.substring(start + 1, current - 1);
addToken(STRING, value);
}
private boolean match(char expected) {
if (isAtEnd()) return false;
if (source.charAt(current) != expected) return false;
current++;
return true;
}
private char peek() {
if (isAtEnd()) return '\0';
return source.charAt(current);
}
private char peekNext() {
if (current + 1 >= source.length()) return '\0';
return source.charAt(current + 1);
}
private boolean isAlpha(char c) {
return (c >= 'a' && c <= 'z') ||
(c >= 'A' && c <= 'Z') ||
c == '_';
}
private boolean isAlphaNumeric(char c) {
return isAlpha(c) || isDigit(c);
}
private boolean isDigit(char c) {
return c >= '0' && c <= '9';
}
private char advance() {
return source.charAt(current++);
}
private void addToken(TokenType type) {
addToken(type, null);
}
private void addToken(TokenType type, Object literal) {
String text = source.substring(start, current);
tokens.add(new Token(type, text, literal, line));
}
}

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src/main/java/com/craftinginterpreters/lox/Token.java Normal file
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package com.craftinginterpreters.lox;
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;
}
}

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src/main/java/com/craftinginterpreters/lox/TokenType.java Normal file
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package com.craftinginterpreters.lox;
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
}