Could not find module: detect root or fail early

Motivation

In a recent stackoverflow question the asker runs into the issue that ghci fails to load a module that seems to be in the right place.

this is my directory´s tree:

• Figures/
  • Point.hs
  • Circle.hs

A minimal example would be the following contents:

-- Point.hs
module Figures.Point where

-- Circle.hs
module Figures.Circle where

import Figures.Point

Now if you are in the Figures directory and call ghci Circle.hs, then you will get an error like:

Circle.hs:3:1: error:
    Could not find module ‘Figures.Point’
    Use -v (or `:set -v` in ghci) to see a list of the files searched for.
  |
3 | import Figures.Point
  | ^^^^^^^^^^^^^^^^^^^^

The issue is that you should run ghci from the parent directory as follows ghci Figures/Circle.hs.

Proposal

I think there are two better ways to deal with this:

1. Detect that Figures.Circle contains the Figures prefix and use that to automatically find the correct root directory and load Figures.Point without issues.

2. Fail early because Figures.Circle does not match the name of the file Circle.hs.

Either of these would be an improvement to the status quo in my opinion, but I prefer option 1 if it is not too difficult.