Elm Compiler "Map.!: given key is not an element in the map"

July 8, 2019

There's an issue with the Elm compiler documented here that results in the error message:

Map.!: given key is not an element in the map

Though it is not resolved, there are a few things you can do to get around it for now:

  1. Don't use Array in a custom type (use List instead)
  2. Try removing elm-stuff and recompile
  3. Compile without the --debug flag

Using Array in a custom type was what led me to the error, and substituting for List made it go away.

Looking forward to updating this post when the issue is resolved!