Renamed to robinheghan/elm-deque. It is published under that name, and new versions come out there.
Versions published as Skinney/elm-deque still install under that name. 2 versions of 3 come from the new location (see their notes). 1 version could not be recovered and cannot be installed.
Rerouted (renamed, verified). The GitHub user or repository was renamed. The tag is still there, at the new name. The Lamdera package server serves a copy recovered from https://github.com/robinheghan/elm-deque.
What we checked: The repo moved to github.com/robinheghan/elm-deque. Rebuilt with git archive from commit 92fb6925dd6e of https://github.com/robinheghan/elm-deque (zip prefix Skinney-elm-deque-92fb692/, America/Los_Angeles times): the zip is byte-identical to the one package.elm-lang.org recorded, SHA-1 4bfb473171f4f859accba0a7317620853ff6ef59.
The Lamdera compiler uses this copy and prints a one-line notice saying so. elm itself fails to download this version.
Details · package.elm-lang.org's zip: https://github.com/Skinney/elm-deque/zipball/1.1.0/
A double ended queue for Elm. Think of it like a List, but with equally fast access to the front and the back (List only has fast access to the front).
This data structure uses a finger tree implementation, and has amortized O(1) operations for access and pop to the front and back portions of the queue. It also provies amortized O(1) concatination/appending.
folkertdev/elm-deque uses a different implementation which, in theory, provides faster pops and pushes, but which will occasionally spend a long time doing each of those due to rebalancing the elements. A finger tree implementation has a higher (but still small) overhead when doing stuff, but has more predictable performance. folkertdev/elm-deque also doesn't provide O(1) concatination/appending.
This implementation doesn't provide all the functions that you find in folkertdev/elm-deque. If that's a problem for you, let me know and I'll provide those functions in this package as well.