Hi!
This is a bunch of koans which can guide you through the process of creating parser combinator in Kotlin from scratch.
This is by no means a course on parsers but more of a very quick intro into the subject. To start with, ask yourself the following questions (this is not a quiz, so not being sure about the answer is perfectly fine):
- What is a grammar? Context-free grammar?
- What is a parser? Parser combinator?
- What is left recursion?
- What is the difference between parse tree and abstract syntax tree?
- How would you write an interpreter to evaluate expressions like "(1 + 2) * 3 - 4"?
- compile the project using Gradle
compileTestKotlintask or IDE - take a look at
src/test/parserkoans/1 - Basic parsers/0 - Parser API.ktto get familiar with core classes - open
src/test/parserkoans/1 - Basic parsers/1 - String parser.kt- run the tests to see them fail with
NotImplementedError - make the first test pass by implementing
TODO() - make the second test pass by adding more functionality
- repeat until all tests in the step are passing
- run the tests to see them fail with
- repeat the above for the next steps
- Parser combinator koans as a Stepik course
- Parser4k - recursive descent parser combinator library for Kotlin with support for left recursion