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//! A mathematical expression parsing and evaluation library.
//!
//! # Evaluating an expression with variables
//!
//! `eval` is perfect for cases when you just need to evaluate an expression
//! once, with a given a set of variables.
//!
//! ```
//! #[macro_use] extern crate asciimath;
//! use asciimath::eval;
//!
//! let expression = "(x + y * 4) ^ 3";
//! let variables = scope!{
//!    "x" => 8,
//!    "y" => 12.25
//! };
//!
//! assert_eq!(Ok(185193.0), eval(expression, &variables));
//! ```
//!
//!
//! # Compiling Expressions for Repeated Evaluation
//!
//! The example below demonstrates parsing and evaluation of an expression
//! with two sets of variables.
//!
//! The Scope is passed to the compiler for disambiguation in cases of
//! implicit multiplication and function calls.
//!
//! ```
//! #[macro_use] extern crate asciimath;
//! use asciimath::{compile,Evaluate};
//!
//! let scope_one = scope!{
//!    "x" => 8,
//!    "y" => 12.25
//! };
//! let scope_two = scope!{
//!    "x" => 3,
//!    "y" => 0
//! };
//! let expression = compile("(x + y * 4) ^ 3", &scope_one).unwrap();
//!
//! assert_eq!(Ok(185193.0), expression.eval_with(&scope_one));
//! assert_eq!(Ok(27.0), expression.eval_with(&scope_two));
//! ```
//!
//! # Custom Functions
//!
//! A lot of effort has been put into making custom functions as easy to write
//! as possible.
//!
//! ```
//! #[macro_use] extern crate asciimath;
//! use asciimath::{eval,CustomFn};
//!
//! let my_sum: CustomFn = |args| Ok(args.iter().sum());
//!
//! let scope = scope!{
//!   "x" => 1,
//!   "my_sum" => my_sum,
//! };
//!
//! assert_eq!(Ok(6.0), eval("my_sum(x, 2, 3)",&scope));
//! ```
//!
//! # Built-in Functions
//!
//! - `cos(x)`
//! - `tan(x)`
//! - `max(a,b,c,...)`
//! - `min(a,b,c,...)`
//! - `abs(x)`
//! - `sqrt(x)`
//! - `cbrt(x)`

#[macro_use]
extern crate lazy_static;

#[macro_use]
mod macros;
mod ast;
mod error;
mod functions;
mod lexer;
mod parser;
mod tokens;

pub use ast::{Evaluate, Scope};
pub use error::Error;
pub use functions::CustomFn;
pub use parser::{compile, eval};