Does fileDatastore not implement "matlab.io.Datastore"?

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I'm currently developing a custom datastore that takes an existing datastore and adds some features.
In the constructor I would like to make sure that a passed argument is of type "matlab.io.Datastore" so I do:
assert(isa(ds, "matlab.io.Datastore"), ...)
This works fine for another custom datastore that directly implements "matlab.io.Datastore" but it does not work when das is created using
ds = fileDatastore(...)
fileDatastore. Form digging around in the source of "matlab.io.datastore.FileDatastore" I found out that it at some point implements "matlab.io.Datastore" but still above is not wokring. Am I missing somehting obvious?

回答(1 个)

Shlok
Shlok 2024-9-4
Hi Eike,
The matlab.io.datastore.FileDatastore class does not implement the matlab.io.Datastore interface. As a result, assert(isa(ds, 'matlab.io.Datastore'), ...) returns false when used for fileDatastore()” instance.
You can verify this by using the superclasses function, which lists all the superclasses of a given class.
superclasses(ds)
Output:
From the output above, you can see that “matlab.io.datastore.FileDatastore” implements “matlab.io.datastore.Datastore” instead of “matlab.io.Datastore”. Therefore, you need to modify the code as follows to return true:
assert(isa(ds, "matlab.io.datastore.Datastore"), ...);
To know more about fileDatastore, refer to the following documentation link:

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