use std::fmt;
use prelude::*;
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash, PartialOrd, Ord)]
pub enum Transient {
Sin,
Cos,
Log,
Exp
}
use self::Transient::*;
#[derive(Debug, Clone, Eq, PartialEq, Hash, PartialOrd, Ord)]
pub enum Func {
Transient(Transient),
Diff(String),
Definition(Vec<String>, NodeRc)
}
impl From<Transient> for Func {
fn from(t: Transient) -> Func {
Func::Transient(t)
}
}
impl fmt::Display for Func {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
use self::Func::*;
match *self {
Transient(t) => {
let name = match t {
Sin => "sin",
Cos => "cos",
Log => "log",
Exp => "exp"
};
f.write_str(name)
},
Diff(ref var) => write!(f, "d/d{}", var),
Definition(ref args, ref expr) => write!(f, "({}) => {}", args.iter().format(", "), expr)
}
}
}