Simplify the derivative of reductions.
Avoid untying the knot.
Simplify the derivative of concatenations.
Name block parameters for autocomplete.
Test reduction compaction.
Attempt at reduction compaction.
Bump Lagrangian so it catches exceptions.
Bump Lagrangian so it catches exceptions.
Pairs.
Pairs are reducible.
Name block parameters.
Count least fixed point iterations under DEBUG.
Pair equality is by receiver properties first.
Pair hashing.
Singleton null pair instance.
Construct (nil, nil) → [HMRPair null].
Pairs are appendable.
Parse trees are made from cons cells.

Oh look, the associativity and all makes sense now!
Don’t compact concatenations of null prefixes.

At least, not this way.
Another named block parameter.