Published as the billstclair/elm-localstorage package at elm-lang.org
This module is built on top of the billstclair/elm-port-funnel package, so it can share two ports with other port funnel modules. It requires Elm 0.19.
I've built many projects that use JavaScript's localStorage mechanism for persistent storage. Enough to know the features I need. This package makes that experience available to the community.
Some ideas here are cribbed from Paul Statezny's knledg/elm-local-storage-ports, but his package is not in the Elm repository. This one also provides an API-compatible pure Elm version that you can use it from elm reactor during development (with only session persistence, but that suffices for development).
See the example directory for use of both simulated ports, which work in elm reactor, and real ports.
The example is live at lisplog.org/localstorage.
To use the real ports with your own application, create the two ports, cmdPort and subPort, as is done in example/Main.elm. Copy the site directory, inluding its js subdirectory. In index.html, change the <title>, and, if necessary change Main to the name of your top-level application module. If you want to use different names for the ports, you can change those here as well.
Finally, compile your application Elm file into site/elm.js:
cd ...
elm make Main.elm --output site/elm.js
Happy hacking!
Bill St. Clair
24 March, 2018