I ran into similar mental difficulty regarding whether type Any is a
superset of any other types. I did not find anything to read, but
simply accepted the fact through painstaking experiments.
I think the word "Any" here is confusing. The English definition of it
means that it ought to include any types. Perhaps we should seek other
word to define this type. Word like "Mixed" might be more appropriate
for this?
On 2014年11月27日 08:17, Patrick O'Leary wrote:
You've hit type invariance. In Julia, parametric types are
invariant--that is, Dict{ASCIIString,Float64} is not a subtype of
Dict{ASCIIString,Any}.
For more information on why we use invariant parametric types, search
the list for "parametric invariant" or similar; there have been a few
discussions on the topic.
Patrick
