Go JSON Parser

This repository contains a JSON parser written in Go, created as part of a learning exercise to understand parsing techniques.

What I Learned

Building this JSON parser provided valuable insights into the fundamental concepts of parsing, including:

• Lexical Analysis: Understanding how to break down a sequence of characters into meaningful tokens.
• Syntactic Analysis: Learning to analyze a list of tokens to match a formal grammar.
• Error Handling: Developing robust error handling to provide useful feedback on invalid JSON structures.

Challenges Faced

Throughout the development process, several challenges were encountered and overcome:

• Tokenization: Designing an efficient lexer to correctly identify and categorize different parts of JSON data.
• Grammar Matching: Implementing a parser that accurately interprets the structure of JSON according to its formal definition.
• Data Types Handling: Ensuring correct parsing and representation of various JSON data types, including strings, numbers, booleans, null values, objects, and arrays.
• Nested Structures: Handling complex nested JSON objects and arrays required careful consideration of recursive parsing techniques.
• Validation and Testing: Creating extensive test cases to validate the parser's accuracy and robustness against both valid and invalid JSON inputs.

Conclusion

This project was an excellent opportunity to delve into the world of parsing and compilers. The knowledge gained from building a JSON parser from scratch is foundational and applicable to more advanced programming challenges, such as developing custom data formats and building compilers.

Structure

The project is structured as follows:

• cmd/json/json-parser.go: This is where the Unmarshal function is located.
• pkg/lexer/lexer.go: This file contains the lexer logic.
• pkg/lexer/lexer_test.go: This file contains the tests for the lexer, including TestLex.
• pkg/parser/parser.go: This file contains the parser logic.
• pkg/parser/parser_test.go: This file contains the tests for the parser, including TestParse.

Usage

To use the JSON parser, you need to call the Unmarshal function from the json-parser.go file in the cmd/json directory.

Testing

To run the tests for the lexer and the parser, navigate to the pkg/lexer and pkg/parser directories respectively and run go test.