lambdas 0.1.0

A library for defining domain specific languages in a polymorphic lambda calculus
Documentation 
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use crate::*;
use std::fmt::Debug;

/// convenience function for returning arguments from a DSL function
pub fn ok<T: Into<Val<D>> , D:Domain>(v: T) -> VResult<D> {
    Ok(v.into())
}

/// convenience function for equality assertions
pub fn assert_eq_val<D:Domain, T>(v: &Val<D>, o: T)
where T: FromVal<D> + Debug + PartialEq,
{
    assert_eq!(T::from_val(v.clone()).unwrap(), o);
}

/// convenience function for asserting that something executes to what you'd expect
pub fn assert_execution<D: Domain, T>(expr: &str, args: &[Val<D>], expected: T)
where T: FromVal<D> + Debug + PartialEq,
{
    let e: Expr = expr.parse().unwrap();
    let mut args: Vec<LazyVal<D>> = args.iter().map(|arg|LazyVal::new_strict(arg.clone())).collect();
    let res = e.eval(e.root(), &mut args, None).unwrap();
    assert_eq_val(&res,expected);
}

pub fn assert_error<D: Domain, T>(expr: &str, args: &[Val<D>], expected_error_msg: String)
where T: FromVal<D> + Debug + PartialEq
{
    let e: Expr = expr.parse().unwrap();
    let mut args: Vec<LazyVal<D>> = args.iter().map(|arg|LazyVal::new_strict(arg.clone())).collect();
    let res = e.eval(e.root(),&mut args, None);
    assert!(res.is_err());
    assert_eq!(expected_error_msg, res.err().unwrap());
}