The Link to 236 points to something else that is not #at:at:
Why are new sub dictionaries instansiated as a normal Dictionary instead of species/class?
I would expect a sub-Dictionary be of the same class as its parent.
Here is a test case:
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| dct key1 key2 subDct |
dct := IdentityDictionary new.
key1 := 'a'.
key2 := key1 copy.
dct
at: #a at: key1 put: 1;
at: #a at: key2 put: 2.
subDct := dct at: #a.
TestCase new
assert: subDct size equals: 2;
assert: (subDct at: key1) equals: 1;
assert: (subDct at: key2) equals: 2
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Best regards,
Henrik