Implement compose operator ∘
Add NONCE ERROR.
Implement monadic ↑ as mix, as in Dyalog.
Implement pick.
Fix pick into empty array.
Implement monadic ↓ as split.
Fix error handling in pick.
Fix interpretation of left argument of pick.
Implement boolean expand on vectors.
Implement expand of high rank arrays.
Add dfns queens example.
Move queens up a level so it appears in the web demo.
Make code font less enormous.
Make code font less enormous.