Dave Angel <da...@davea.name> Wrote in message: > "Clayton Kirkwood" <c...@godblessthe.us> Wrote in message: >> >> >> !-----Original Message----- >> !From: Tutor [mailto:tutor-bounces+crk=godblessthe...@python.org] On >> !Behalf Of Steven D'Aprano > ... >> >> For clarification, a key only has one value which can be changed. > > No, because the key has to be immutable, like a string or an int.
My error for reading your statement wrong. > >> Multiple >> keys can have the same value (hopefully not to the same memory location, >> because one would usually not want the change of one key's value to alter >> another key's value. As to the hash table, yes, I agree that this would be >> one to many, hence the chains. > > Memory locations are an implementation detail. We're talking in > this paragraph about keys and values. A value is an object, the > dict provides a one-way mapping from immutable key to an > arbitrary value object. If the value objects happen to be > immutable, it makes no difference if a program uses the same > value for multiple keys. If the values are not immutable, python > makes no assurance whether two values are equal, or identical. If > the latter is undesirable for a particular use, it's up to the > application logic to prevent it. It's probably more often useful > than problematic. Python makes no such assurances. > > > > > >> !Can you give a concrete example of what you're trying to do? >> >> The changing of the order is necessary when you want numeric indexing, say >> for columns or rows. >> > > No idea how this relates to dicts, which have no order, nor rows > nor columns. Make it concrete. > > > -- > DaveA > > _______________________________________________ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > https://mail.python.org/mailman/listinfo/tutor > > -- DaveA _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor