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no tuple.copy() - Skaperen - Apr-30-2022
why is there no
.copy() method for a tuple? but i can make a shallow copy using [:].
RE: no tuple.copy() - buran - May-04-2022
it's immutable. why would you need a copy? Reference is good enough.
there is no e.g.
str.copy either :-)Note that with
[:] it's the same object (same id), not a copyPython 3.9.4 (default, Apr 9 2021, 01:15:05) [GCC 5.4.0 20160609] on linux Type "help", "copyright", "credits" or "license" for more information. >>> spam = (1, 2, 3) >>> eggs = spam[:] >>> id(spam) 139751983214912 >>> id(eggs) 139751983214912 >>>
RE: no tuple.copy() - ndc85430 - May-04-2022
Immutability is the reason for having a
copy in the first place. How else are you going to produce an updated version?
RE: no tuple.copy() - buran - May-04-2022
(May-04-2022, 05:31 AM)ndc85430 Wrote: Immutability is the reason for having a copy in the first place. How else are you going to produce an updated version?Creating a copy of immutable object will create new immutable object identical to the original one (that is assuming there are indeed 2 objects with different ids), which you will not be able to modify anyway - hence there is no need to keep 2 identical immutable objects in memory. As I show, creating a new "copy" via slicing is in fact just new reference to the same object. You suggest that at some point during the creation of a copy, the new object will be mutable.
Depending on what means "updated" version there would be different approaches, e.g. comprehension. But
copy method definitely will not do.
RE: no tuple.copy() - Skaperen - May-04-2022
(May-04-2022, 05:31 AM)ndc85430 Wrote: Immutability is the reason for having a copy in the first place. How else are you going to produce an updated version?
the copy will also be immutable. how are you going to update it?