Fix ControlLinearNode Overshadowing

[alexbeattie42]

Fixes issue #4095

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[alexbeattie42]

@nickbianco is this a suitable fix for the compiler warning?

[nickbianco]

@alexbeattie42 let's try overriding Object's virtual methods to see if that resolves the compiler warnings.

Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @alexbeattie42)

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OpenSim/Simulation/Control/ControlLinearNode.h line 99 at r1 (raw file):

    ControlLinearNode& operator=(const ControlLinearNode &aControl);
    bool operator==(const ControlLinearNode &aControl) const;
    bool operator<(const ControlLinearNode &aControl) const;

I think we should only need to add override calls to Objects virtual methods. We should be able to leave the copy assignment operator for ControlLinearNode as-is since it not a virtual method of Object.

Suggestion:

    ControlLinearNode& operator=(const ControlLinearNode &aControl);
    bool operator==(const ControlLinearNode &aControl) const override;
    bool operator<(const ControlLinearNode &aControl) const override;

[alexbeattie42]

OpenSim/Simulation/Control/ControlLinearNode.h line 99 at r1 (raw file):

Previously, nickbianco (Nick Bianco) wrote…

I think we should only need to add override calls to Objects virtual methods. We should be able to leave the copy assignment operator for ControlLinearNode as-is since it not a virtual method of Object.

If I make this change clang complains that:
Only virtual member functions can be marked 'override'

[alexbeattie42]

I tried the suggested approach and clang is not happy with it sadly.

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @nickbianco)

[nickbianco]

Ah, that is because the signatures are different. To truly satisfy Object's interface, you would need to override the operators using Object types instead of ControlLinearNode:

bool operator==(const Object& other) const override;
bool operator<(const Object& other) const override;

This is an odd quirk of polymorphism that I hadn't considered before. I suppose you could do that, but then you would need to dynamic_cast to ControlLinearNode internally which seems hacky. But I'm not sure having using Object::operator== is ideal either.