Eiffel: a way to call precursor redefined feature on another function

Question

I'm looking for a way to call Precursor on another feature. The context is that I redefine a routine calling another heir's feature that calls mine, and I'd like to call it explicitly. Is there a way to do something such as in java Precursor.feature_a.

If not, the only alternative I find is to write a feature_a_implementation and call it from redefined feature. Is there a particular reason not to have this mechanism? The consequences of doing that would be to define 2 times the contract of feature_a into feature_a and feature_a_implementation

score 2 · Accepted Answer · answered Aug 28 '19 at 14:34

Feature replication can be used for that:

class A feature
    f do print ("A") end
end

class B inherit
    A redefine f select f end
    A rename f as g end
feature
    f do print ("B") end
    h do g end
end

Feature f of class A appears in class B twice: under name f (the redefined and selected version) and under name g (the original version). The feature h calls g and prints A as expected.

Eiffel: a way to call precursor redefined feature on another function

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