Build parsers in Java with composable parser combinators. Use parseWorks to express grammars in code, get clear error messages, and keep your parsers fast and testable.

• Compose parsers with a small set of powerful combinators.
• Get precise, readable error messages for parse failures.
• Write thread-safe code with immutable parsers and inputs.
• Keep dependencies minimal (only JUnit in tests).
• Avoid left-recursion pitfalls with built-in protection.
• Detect infinite loops on empty input.

Requirements: Java 17 or higher.

Maven (latest release):

<dependency>
    <groupId>io.github.parseworks</groupId>
    <artifactId>parseworks</artifactId>
    <version>3.0.0</version>
    <scope>compile</scope>
</dependency>

Gradle:

repositories {
  maven { url 'https://central.sonatype.com/repository/maven/' }
}

dependencies {
  implementation 'io.github.parseworks:parseworks:3.0.0'
}

Use parser combinators to build a simple addition parser:

import io.github.parseworks.parsers.Lexical;

import static io.github.parseworks.parsers.Numeric.*;

// Define a parser for a simple addition expression
Parser<Character, Integer> sum =
    Numeric.number.thenSkip(Lexical.chr('+')).then(number).map(Integer::sum);

    // Parse the input "1+2"
    int value = sum.parse(Input.of("1+2")).value();
assert value ==3;

    // Handle a parsing error
    String message = sum.parse(Input.of("1+z")).handle(
        success -> "Match: " + success,
        failure -> "Error: " + failure.error()
    );
// Example output contains: "Error: Parse error at line 1 position 3"

• Read the User guide to get started.
• Explore the Advanced user guide for complex patterns and performance tips.
• Follow the Parser design guide to plan and implement robust parsers.

parseWorks is available under the MIT License.