This page is a snapshot from the LWG issues list, see the Library Active Issues List for more information and the meaning of C++11 status.
Section: 29.8.12 [numeric.iota] Status: C++11 Submitter: Daniel Krügler Opened: 2008-08-20 Last modified: 2016-02-10
Priority: Not Prioritized
View all issues with C++11 status.
According to the recent WP N2691, 29.8.12 [numeric.iota]/1, the requires clause of std::iota says:
T shall meet the requirements of CopyConstructible and Assignable types, and shall be convertible to ForwardIterator's value type.[..]
Neither CopyConstructible nor Assignable is needed, instead MoveConstructible seems to be the correct choice. I guess the current wording resulted as an artifact from comparing it with similar numerical algorithms like accumulate.
Note: If this function will be conceptualized, the here proposed MoveConstructible requirement can be removed, because this is an implied requirement of function arguments, see N2710/[temp.req.impl]/3, last bullet.
[ post San Francisco: ]
Issue pulled by author prior to review.
[ 2009-07-30 Daniel reopened: ]
with the absence of concepts, this issue (closed) is valid again and I suggest to reopen it. I also revised by proposed resolution based on N2723 wording:
[ 2009-10 Santa Cruz: ]
Change 'convertible' to 'assignable', Move To Ready.
Change the first sentence of 29.8.12 [numeric.iota]/1:
Requires: T shall
meet the requirements of CopyConstructible and Assignable types, and shallbe assignable to ForwardIterator's value type. [..]