New iterator requirements
I noticed that most if not all containers now require their ::iterator type to satisfy LegacySomethingIterator instead of SomethingIterator.
For example, std::vector<>::iterator now requires:
iteratorLegacyRandomAccessIterator
This seems to be the same for most of the other containers, all requiring their iterators to go from SomethingIterator to LegacySomethingIterator.
There are also the "new" requirements that took the names of the old requirements, such as RandomAccessIterator, why were these added? It seems to me that the new variants just shadow the legacy variants, no differences.
Why were new ones created in the first place, their requirements look the same to me. Why don't the new ones just replace the old requirements instead of right now having 2 different names for them (e.g. RandomAccessIterator and LegacyRandomAccessIterator)?
c++ c++-concepts c++20
edited 2 hours ago
Will Vousden
24.6k86186
asked 2 hours ago
Sombrero Chicken
23.2k33076
add a comment |
I noticed that most if not all containers now require their ::iterator type to satisfy LegacySomethingIterator instead of SomethingIterator.
For example, std::vector<>::iterator now requires:
iteratorLegacyRandomAccessIterator
This seems to be the same for most of the other containers, all requiring their iterators to go from SomethingIterator to LegacySomethingIterator.
There are also the "new" requirements that took the names of the old requirements, such as RandomAccessIterator, why were these added? It seems to me that the new variants just shadow the legacy variants, no differences.
Why were new ones created in the first place, their requirements look the same to me. Why don't the new ones just replace the old requirements instead of right now having 2 different names for them (e.g. RandomAccessIterator and LegacyRandomAccessIterator)?
c++ c++-concepts c++20
edited 2 hours ago
Will Vousden
24.6k86186
asked 2 hours ago
Sombrero Chicken
23.2k33076
Note that the old and new iterator requirements do have some differences: Why aren't ranges' algorithms compatible with std's iterators?
– cpplearner
1 hour ago
add a comment |
I noticed that most if not all containers now require their ::iterator type to satisfy LegacySomethingIterator instead of SomethingIterator.
For example, std::vector<>::iterator now requires:
iteratorLegacyRandomAccessIterator
This seems to be the same for most of the other containers, all requiring their iterators to go from SomethingIterator to LegacySomethingIterator.
There are also the "new" requirements that took the names of the old requirements, such as RandomAccessIterator, why were these added? It seems to me that the new variants just shadow the legacy variants, no differences.
Why were new ones created in the first place, their requirements look the same to me. Why don't the new ones just replace the old requirements instead of right now having 2 different names for them (e.g. RandomAccessIterator and LegacyRandomAccessIterator)?
c++ c++-concepts c++20
edited 2 hours ago
Will Vousden
24.6k86186
asked 2 hours ago
Sombrero Chicken
23.2k33076
I noticed that most if not all containers now require their ::iterator type to satisfy LegacySomethingIterator instead of SomethingIterator.
For example, std::vector<>::iterator now requires:
iteratorLegacyRandomAccessIterator
This seems to be the same for most of the other containers, all requiring their iterators to go from SomethingIterator to LegacySomethingIterator.
There are also the "new" requirements that took the names of the old requirements, such as RandomAccessIterator, why were these added? It seems to me that the new variants just shadow the legacy variants, no differences.
Why were new ones created in the first place, their requirements look the same to me. Why don't the new ones just replace the old requirements instead of right now having 2 different names for them (e.g. RandomAccessIterator and LegacyRandomAccessIterator)?
c++ c++-concepts c++20
c++ c++-concepts c++20
edited 2 hours ago
Will Vousden
24.6k86186
asked 2 hours ago
Sombrero Chicken
23.2k33076
edited 2 hours ago
Will Vousden
24.6k86186
asked 2 hours ago
Sombrero Chicken
23.2k33076
edited 2 hours ago
Will Vousden
24.6k86186
edited 2 hours ago
Will Vousden
24.6k86186
edited 2 hours ago
Will Vousden
24.6k86186
24.6k86186
asked 2 hours ago
Sombrero Chicken
23.2k33076
asked 2 hours ago
Sombrero Chicken
23.2k33076
asked 2 hours ago
Sombrero Chicken
23.2k33076
23.2k33076
Note that the old and new iterator requirements do have some differences: Why aren't ranges' algorithms compatible with std's iterators?
– cpplearner
1 hour ago
add a comment |
Note that the old and new iterator requirements do have some differences: Why aren't ranges' algorithms compatible with std's iterators?
– cpplearner
1 hour ago
Note that the old and new iterator requirements do have some differences: Why aren't ranges' algorithms compatible with std's iterators?
– cpplearner
1 hour ago
Note that the old and new iterator requirements do have some differences: Why aren't ranges' algorithms compatible with std's iterators?
– cpplearner
1 hour ago
add a comment |
1 Answer
1
active
oldest
votes
These are not new things, hence the term "legacy". This is simply how the cppreference site chooses to reconcile the fact that C++20 will have two different things that are both "concepts" called "RandomAccessIterator".
Pre-C++20, a "concept" was just a set of requirements in the standard that represented the behavior expected of certain template parameters. In C++20, with concepts becoming an actual language feature, that needed to shift. The problem is that the Ranges concept of "RandomAccessIterator" is not the same as the old-style "concept" of "RandomAccessIterator".
Since C++ considers them both to be "concepts" (though only the newer one is a concept in the language sense), they would both have the same page name on the Wiki. And MediaWiki doesn't really allow that.
So the maintainers of the site settled on using "Legacy" to differentiate them. Note that the actual standard doesn't use this "Legacy" prefix.
answered 2 hours ago
Nicol Bolas
282k33464640
Haha that's funny. I actually edited out that part. My initial post had another question asking if the standard uses the term LegacyIterator but then I thought to myself it has to be because cppreference is always very standard compliant. Guess not in this case, thanks :)
– Sombrero Chicken
2 hours ago
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
These are not new things, hence the term "legacy". This is simply how the cppreference site chooses to reconcile the fact that C++20 will have two different things that are both "concepts" called "RandomAccessIterator".
Pre-C++20, a "concept" was just a set of requirements in the standard that represented the behavior expected of certain template parameters. In C++20, with concepts becoming an actual language feature, that needed to shift. The problem is that the Ranges concept of "RandomAccessIterator" is not the same as the old-style "concept" of "RandomAccessIterator".
Since C++ considers them both to be "concepts" (though only the newer one is a concept in the language sense), they would both have the same page name on the Wiki. And MediaWiki doesn't really allow that.
So the maintainers of the site settled on using "Legacy" to differentiate them. Note that the actual standard doesn't use this "Legacy" prefix.
answered 2 hours ago
Nicol Bolas
282k33464640
Haha that's funny. I actually edited out that part. My initial post had another question asking if the standard uses the term LegacyIterator but then I thought to myself it has to be because cppreference is always very standard compliant. Guess not in this case, thanks :)
– Sombrero Chicken
2 hours ago
add a comment |
These are not new things, hence the term "legacy". This is simply how the cppreference site chooses to reconcile the fact that C++20 will have two different things that are both "concepts" called "RandomAccessIterator".
Pre-C++20, a "concept" was just a set of requirements in the standard that represented the behavior expected of certain template parameters. In C++20, with concepts becoming an actual language feature, that needed to shift. The problem is that the Ranges concept of "RandomAccessIterator" is not the same as the old-style "concept" of "RandomAccessIterator".
Since C++ considers them both to be "concepts" (though only the newer one is a concept in the language sense), they would both have the same page name on the Wiki. And MediaWiki doesn't really allow that.
So the maintainers of the site settled on using "Legacy" to differentiate them. Note that the actual standard doesn't use this "Legacy" prefix.
answered 2 hours ago
Nicol Bolas
282k33464640
Haha that's funny. I actually edited out that part. My initial post had another question asking if the standard uses the term LegacyIterator but then I thought to myself it has to be because cppreference is always very standard compliant. Guess not in this case, thanks :)
– Sombrero Chicken
2 hours ago
add a comment |
These are not new things, hence the term "legacy". This is simply how the cppreference site chooses to reconcile the fact that C++20 will have two different things that are both "concepts" called "RandomAccessIterator".
Pre-C++20, a "concept" was just a set of requirements in the standard that represented the behavior expected of certain template parameters. In C++20, with concepts becoming an actual language feature, that needed to shift. The problem is that the Ranges concept of "RandomAccessIterator" is not the same as the old-style "concept" of "RandomAccessIterator".
Since C++ considers them both to be "concepts" (though only the newer one is a concept in the language sense), they would both have the same page name on the Wiki. And MediaWiki doesn't really allow that.
So the maintainers of the site settled on using "Legacy" to differentiate them. Note that the actual standard doesn't use this "Legacy" prefix.
answered 2 hours ago
Nicol Bolas
282k33464640
These are not new things, hence the term "legacy". This is simply how the cppreference site chooses to reconcile the fact that C++20 will have two different things that are both "concepts" called "RandomAccessIterator".
Pre-C++20, a "concept" was just a set of requirements in the standard that represented the behavior expected of certain template parameters. In C++20, with concepts becoming an actual language feature, that needed to shift. The problem is that the Ranges concept of "RandomAccessIterator" is not the same as the old-style "concept" of "RandomAccessIterator".
Since C++ considers them both to be "concepts" (though only the newer one is a concept in the language sense), they would both have the same page name on the Wiki. And MediaWiki doesn't really allow that.
So the maintainers of the site settled on using "Legacy" to differentiate them. Note that the actual standard doesn't use this "Legacy" prefix.
answered 2 hours ago
Nicol Bolas
282k33464640
answered 2 hours ago
Nicol Bolas
282k33464640
answered 2 hours ago
Nicol Bolas
282k33464640
answered 2 hours ago
Nicol Bolas
282k33464640
282k33464640
Haha that's funny. I actually edited out that part. My initial post had another question asking if the standard uses the term LegacyIterator but then I thought to myself it has to be because cppreference is always very standard compliant. Guess not in this case, thanks :)
– Sombrero Chicken
2 hours ago
add a comment |
Haha that's funny. I actually edited out that part. My initial post had another question asking if the standard uses the term LegacyIterator but then I thought to myself it has to be because cppreference is always very standard compliant. Guess not in this case, thanks :)
– Sombrero Chicken
2 hours ago
Haha that's funny. I actually edited out that part. My initial post had another question asking if the standard uses the term LegacyIterator but then I thought to myself it has to be because cppreference is always very standard compliant. Guess not in this case, thanks :)
– Sombrero Chicken
2 hours ago
Haha that's funny. I actually edited out that part. My initial post had another question asking if the standard uses the term LegacyIterator but then I thought to myself it has to be because cppreference is always very standard compliant. Guess not in this case, thanks :)
– Sombrero Chicken
2 hours ago
add a comment |
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Note that the old and new iterator requirements do have some differences: Why aren't ranges' algorithms compatible with std's iterators?
– cpplearner
1 hour ago