Crate emp

EMP

NOTICE: EMP 1.1.x is not compatable with data from EMP 1.0.x!

EMP is a bytecode format which is able to pack JSON and NBT data into an even smaller file size, which is useful for storage of large amounts of data.

Rust structure

pub enum Value {
  Null,
  Object(std::collections::HashMap<std::string::String, Value>),
  Array(std::vec::Vec<Value>),
  String(std::string::String),
  Bit(bool),
  Boolean(bool),
  Int32(i32),
  Float(f32),
  Double(f64),
  Int64(i64),
  Int16(i16),
  Int8(i8),
}

Encoding

Using emp::encode::encode you can pass in an emp::value::Value and get an std::vec::Vec<u8> back, this will encode the data in the Value into the bytes that you can then write to a file.

Decoding

Using emp::decode::decode you can pass in a &[u8] and get an Result<emp::value::Value, emp::errors::DecodeError> in return.

DecodeError is an enum that is as so:

pub enum DecodeError {
  UnexpectedByte(u8, u64),
  EOFError,
  UnmatchedKey(std::string::String),
  StringDecodeError(std::str::Utf8Error),
}

You can also use emp::decode::decode_safe and pass in the same data to decode the data in the same way but if there is an Err it instead returns emp::value::Value::Null.

Parsing

Using the emp::value::parse::from_str function you can pass in a &str to convert it into a Result<emp::value::Value, emp::errors::ParseError>. Alternatively you can use emp::value::parse::from_str_safe and pass in the same thing to get a emp::value::Value, if an error is encounted it returns a emp::value::Value::Null instead.

ParseError is an enum that is as so:

pub enum ParseError {
   EOFError,
   UnexpectedCharacterError(char),
   UnexpectedTokenError(std::string::String),
   InvalidKeyError(value::Value),
   InvalidNumberError(char),
}

JSON Compatability

Conversion

This crate is compatible with serde_json, by using emp::value::json::from_json you can convert a serde_json::Value to an emp::value::Value, vice versa for emp::value::json::to_json.

Encoding

Using emp::encode::json::encode_json you can encode a serde_json::Value directly into emp bytecode.

Decoding

Using emp::decode::json::decode_json you can decode emp bytecode directly into a serde_json::Value, this uses decode_safe rather than decode. You can also use emp::decode::json::decode_json_unsafe to get the error instead of a serde_json::Value::Null

String representation

Strings: Data in quotes Int32: Regular number Int16: Number with s appended at the end Int8: Number with B appended at the end Bit: 0 or 1 with b appended at the end Int64: Number with l appended at the end Boolean: true or false Null: null Array: Values separated by commas in square brackets Object: String then a colon then a Value, separated by commas in curly brackets

Modules

constants

Constants for internal use

decode

Decoding EMP Bytecode

encode

Encoding Values into EMP Bytecode

errors

When Decoding or Parsing encounters something wrong

value

EMP Enum to manipulate in rust