Abstract toMatching and matchCdOdSolution over hardcoded CD/OD counts

[Copilot]

Abstracts the toMatching and matchCdOdSolution functions to work with variable numbers of class and object diagrams, instead of being hard-coded to 2 CDs and 5 ODs.

Changes Made

• toMatching: Now takes a list of CD keys [Int] as a parameter instead of hard-coding [1, 2]. Uses M.toList m to iterate directly over key-value pairs, avoiding repeated M.lookup calls and the Maybe wrapper for improved efficiency.

• matchCdOdSolution: Now derives CD keys from the instance's diagrams field using M.map (const []) (diagrams task) instead of hard-coding [(1, []), (2, [])].

• Call site: Updated matchCdOdEvaluation to pass M.keys $ diagrams task (the actual CD keys) to toMatching.

These changes ensure the evaluation and solution logic correctly handles instances with different numbers of diagrams while improving performance by eliminating repeated map lookups.

Testing

• ✅ Code compiles successfully
• ✅ All targeted tests pass (10 examples, 0 failures)
• ✅ EditorConfig compliance verified
• ✅ HLint shows no issues

The changes maintain clean, idiomatic Haskell code while properly abstracting over the number of diagrams and improving efficiency.

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[jvoigtlaender]

@copilot: For the cds in toMatching, the derivation from M.elems m can be wrong sometimes. Instead, abstract that function explicitly over the original number 2 (now making this a parameter of the function).

[Copilot]

@copilot: For the cds in toMatching, the derivation from M.elems m can be wrong sometimes. Instead, abstract that function explicitly over the original number 2 (now making this a parameter of...

Changed toMatching to take an explicit Int parameter for the number of CDs, using take numberOfCds [1 ..] instead of deriving from M.elems m. Also simplified matchCdOdSolution to use M.map (const []) (diagrams task). Commit: 8bb4c62

[Copilot]

Pull request overview

This PR updates the MatchCdOd task’s evaluation/solution logic to work with the actual set of class-diagram keys in the instance, instead of assuming exactly two CDs (and a fixed OD set), making the code resilient to instances with variable diagram counts.

Changes:

• Generalized toMatching to accept the list of CD keys and to iterate via M.toList over OD mappings.
• Updated matchCdOdEvaluation to pass M.keys (diagrams task) into toMatching.
• Updated matchCdOdSolution to derive CD keys from diagrams task instead of hard-coding [(1, []), (2, [])].

[Copilot]

The new abstraction for variable CD keys/OD keys (in toMatching and matchCdOdSolution) isn’t covered by the existing MatchCdOdSpec tests (they mostly cover instance generation and getODInstances). Consider adding a unit test that constructs a MatchCdOdInstance with non-default diagrams keys (e.g., 3+ CDs and/or non-1/2 keys) and asserts matchCdOdSolution/toMatching produce the expected mappings.

[Copilot]

reverseMapping = fmap (fmap Letters) ... looks ill-typed / incorrect here: M.foldrWithKey builds a Map Int String (via M.adjust (x:) onto []), so you only need to wrap each String once (e.g., fmap Letters/M.map Letters). The extra inner fmap tries to map Letters over the characters of the String and should not typecheck / would produce the wrong shape.

Suggested change

	reverseMapping = fmap (fmap Letters) . M.foldrWithKey
	reverseMapping = fmap Letters . M.foldrWithKey

[jvoigtlaender]

If that problem were real, it would show up as a compiler error ...