Support Stringer for ChainIter and MapIter

[BooleanCat]

Please provide a brief description of the change.

Support Stringer representation for ChainIter and MapIter. This PR is a demonstration of the general pattern of string representations for Iterators that yield generic values (unlike Counter that always yields an int).

Which issue does this change relate to?

81

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[BooleanCat]

@myusko What do you think of this format for iterators that yield generic values?

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[BooleanCat]

I'm not sure if I prefer Iterator<Map, type=string> or Iterator<Map, type=(int, string)>. Since the underlying iterator doesn't matter, perhaps the unput type for maps isn't important and I should only print the output type.

[myusko]

I'm not sure if I prefer Iterator<Map, type=string> or Iterator<Map, type=(int, string)>. Since the underlying iterator doesn't matter, perhaps the unput type for maps isn't important and I should only print the output type.

Yes, I support your idea, that it would be better to print the output format, e.g Iterator<Map, type=string> and I can beat that someone will be slightly confused with the Iterator<Map, type=(int, string)> format, someone will consider the Map as not a function that doing something with the input, but as a real hash table with (key, value) in our case (int, string)

🙂