Revert "placeholders for monad"

This reverts commit ce111e5a7d5d7d2b379e5cac2aa55c49a5b4e547.
Revert "renamed dcell to pcell"

This reverts commit eb0e030e84b49b1c13b1483dee4968651b6b04fb.
Revert "actually returning promises"

This reverts commit 0b341e04aa229f480f5ad7083ee40391e330a341.
structure notes
fixed append