ksl 0.1.30

KSL core library and interpreter
Documentation 
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//! # ksl::builtin::ano
//!
//! Built-in function `And` and `Or`.

use crate::{Environment, FALSE_SYMBOL, TRUE_SYMBOL, eval::apply::eval_apply, value::Value};

pub(crate) fn builtin(args: &[Value], is_and: bool, env: Environment) -> Result<Value, std::sync::Arc<str>> {
    if let [v1, v2] = args {
        match eval_apply(v1, env.clone())? {
            p @ Value::Atom(_) if (is_and && p == *FALSE_SYMBOL) || (!is_and && p == *TRUE_SYMBOL) => Ok(p),
            p @ Value::Atom(_) if (is_and && p == *TRUE_SYMBOL) || (!is_and && p == *FALSE_SYMBOL) => eval_apply(v2, env),

            e => Err(std::sync::Arc::from(format!(
                concat!(
                    "Error[ksl::builtin::{}]: ",
                    "Expected a boolean, but got: `{}`."
                ),
                if is_and { "And" } else { "Or" },
                e
            ))),
        }
    } else {
        Err(std::sync::Arc::from(format!(
            concat!(
                "Error[ksl::builtin::{}]: ",
                "Expected 2 parameters, but {} were passed."
            ),
            if is_and { "And" } else { "Or" },
            args.len()
        )))
    }
}