A monadic (I think...) recursive-descent parser combinator written in Kotlin
Kudzu is a recursive-descent parser written in Kotlin, inspired by Parsec, with the goal of immutability, simplicity, testability, and multiplatform usability. It's designed to be a simple starting place for writing smaller parsers to evaluate relatively simple grammars for other Copper-Leaf libraries, but flexible enough to be used for larger languages.
Notable features:
- Multiplatform targets: JVM, Android, JS Legacy, JS IR, iOS
- No separate lexer/parser. You really just don't need it, so Kudzu omits it
- Parser combinator structure means every piece of your grammar is a complete parser, and thus smaller parsing units can be tested in isolation, but the combination of them creates the full language
- Everything in Kudzu is immutable, and thus fully thread-safe
- Built on top of DeepRecursiveFunction to provide readable stacktraces and prevent StackOverflowErrors
- No complicated DSL or arcane combinator operators required, just normal, readable Kotlin classes. You don't need a Ph.D. in computational linguistics or functional programming to understand a Kudzu parser
- Many useful combinators provided out of the box
- Boolean, Int, Double literals
- String and Character literals, with standard escaped characters (i.e. \n) and Unicode sequences (i.e. \u00A2)
- Identifiers
- Choice, repetition, optional higher-kinded parsers
- Parses input to an Abstract Syntax Tree (AST) and provides facilities for simplifying and/or introspecting the AST
- Line- and column-number source tracking
- Generic expression parser with all the fixin's
- Customizable operator precedence
- Operators with prefix, postfix, and infix with both left- and right-recursive associativity
- Parentheses
- Simplify deeply-nested expressions AST to simpler representation
| Platform |
|---|
| Android |
| JVM |
| iOS |
| JS |
repositories {
mavenCentral()
}
// for plain JVM or Android projects
dependencies {
implementation("io.github.copper-leaf:kudzu-core:{{site.version}}")
}
// for multiplatform projects
kotlin {
sourceSets {
val commonMain by getting {
dependencies {
implementation("io.github.copper-leaf:kudzu-core:{{site.version}}")
}
}
}
}See the website for detailed documentation and usage instructions.
Kudzu is licensed under the BSD 3-Clause License, see LICENSE.md.