//! # KSQL
//!
//! Is a JSON data expression lexer, parser, cli and library.
//!
//! #### Expressions
//! Expressions support most mathematical and string expressions see the `lexer` module for details of the lexer support and rules.
//!
//! ```rust
//! use ksql::parser::{Parser, Value};
//! use std::error::Error;
//!
//! fn main() -> Result<(), Box<dyn Error>>{
//! let src = r#"{"name":"MyCompany", "properties":{"employees": 50}"#.as_bytes();
//! let ex = Parser::parse(".properties.employees > 20")?;
//! let result = ex.calculate(src)?;
//! assert_eq!(Value::Bool(true), result);
//! Ok(())
//! }
//! ```
//!
//!
/// KSQL Expression lexer
/// KSQL Expression parser