This also eliminates the ctad wrapper for Stack: I think the leaning is to remove it. It felt worth keeping the constructor because constructing with a single element is a common use-case.
Adds a single-argument constructor for Scope because the `std::list<std::string>()` is common, and eliding it is consistent with what we've done for things like tuples.
I was considering a vector constructor due to the double-Push on line 1139, but thought the Push() semantics may mean that it's better not to provide.
I think Stack used to use ListNode, but you'd previously removed that dependency. This finalizes the split, and merges ListNode so that we don't accidentally accrue more dependencies. In part I think we'll eventually want to change how Dictionary is set up.
* improve abstraction for AssocList, fix bug in optional else
* add flag for tracing output, clean up code for output
* turned off tracing by default, updated goldens, removed two examples that use pointers, shouldn't have been there yet
Replaces low-level uses of `Cons` with a first-class `Stack` data structure. Also removes an unused algorithm.
Co-authored-by: Jeremy Siek <jsiek@indiana.edu>
Possible next step: use `std::stack` instead.