mamba 0.3.6

A transpiler which converts Mamba files to Python 3 files
Documentation 
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use crate::check::constrain::constraint::Constraint;
use crate::check::constrain::constraint::expected::Expect::{Access, Expression, Function, Type};
use crate::check::constrain::constraint::iterator::Constraints;
use crate::check::constrain::Unified;
use crate::check::constrain::unify::expression::sub;
use crate::check::constrain::unify::finished::Finished;
use crate::check::constrain::unify::function::unify_function;
use crate::check::constrain::unify::ty::unify_type;
use crate::check::context::Context;
use crate::check::name::ContainsTemp;

/// Unifies all constraints.
///
/// We use a mutable reference to constraints for performance reasons.
/// Otherwise, we have to make a entirely new copy of the list of all
/// constraints each time we do a recursive call to unify link.
pub fn unify_link(constraints: &mut Constraints, finished: &mut Finished, ctx: &Context, total: usize) -> Unified {
    if let Some(constraint) = &constraints.pop_constr() {
        let (left, right) = (&constraint.parent, &constraint.child);

        let pos = format!("{}={} ", left.pos, right.pos);
        let count = if constraints.len() <= total { total - constraints.len() } else { 0 };
        let unify = format!("{count}\\{total}");
        let msg =
            if constraint.msg.is_empty() { String::new() } else { format!(" {}", constraint.msg) };

        trace!("{:width$}[{}{}]  {}", pos, unify, msg, constraint, width = 27);

        if let Type { name } = &left.expect {
            if !name.contains_temp() { finished.push_ty(ctx, right.pos, right, name)?; }
        }
        if let Type { name } = &right.expect {
            if !name.contains_temp() { finished.push_ty(ctx, left.pos, left, name)?; }
        }

        match (&left.expect, &right.expect) {
            // trivially equal
            (left, right) if left == right => unify_link(constraints, finished, ctx, total),

            (Function { .. }, Type { .. }) | (Type { .. }, Function { .. })
            | (Access { .. }, _) | (_, Access { .. }) => {
                unify_function(constraint, constraints, finished, ctx, total)
            }

            (Expression { .. }, _) => {
                sub(constraints, right, left, count, total)?;
                unify_link(constraints, finished, ctx, total)
            }
            (_, Expression { .. }) => {
                sub(constraints, left, right, count, total)?;
                unify_link(constraints, finished, ctx, total)
            }

            (Type { .. }, _) | (_, Type { .. }) => {
                unify_type(constraint, constraints, finished, ctx, total)
            }

            _ => {
                reinsert(constraints, constraint, total)?;
                unify_link(constraints, finished, ctx, total + 1)
            }
        }
    } else {
        Ok(finished.clone())
    }
}

/// Reinsert constraint.
///
/// The amount of attempts is a counter which states how often we allow
/// reinserts.
pub fn reinsert(constr: &mut Constraints, constraint: &Constraint, total: usize) -> Unified<()> {
    let pos = format!("({}={}) ", constraint.parent.pos.start, constraint.child.pos.start);
    let count = format!("[reinserting {}\\{}] ", total - constr.len(), total);
    trace!("{:width$}{}{}", pos, count, constraint, width = 17);

    constr.reinsert(constraint)?;
    Ok(())
}