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Section: 22.9.2.2 [bitset.cons], 22.9.2.3 [bitset.members], 23.4.3.3 [string.cons], 23.4.3.7 [string.modifiers], 23.4.3.8 [string.ops] Status: C++17 Submitter: Frank Birbacher Opened: 2013-04-18 Last modified: 2017-07-30
Priority: 3
View all other issues in [bitset.cons].
View all issues with C++17 status.
Discussion:
Similar to LWG 2207 there are several other places where the "Requires" clause precludes the "Throws" condition. Searching for the out_of_range exception to be thrown, the following have been found (based on the working draft N3485):
22.9.2.2 [bitset.cons] p3+4
22.9.2.3 [bitset.members] p13+14 (set)
22.9.2.3 [bitset.members] p19+20 (reset)
22.9.2.3 [bitset.members] p27+28 (flip)
22.9.2.3 [bitset.members] p41+42 (test)
23.4.3.3 [string.cons] p3+4
23.4.3.7.2 [string.append] p3+4
23.4.3.7.3 [string.assign] p4+5
23.4.3.7.4 [string.insert] p1+2, p5+6, p9+10 (partially)
23.4.3.7.5 [string.erase] p1+2
23.4.3.7.6 [string.replace] p1+2, p5+6, p9+10 (partially)
23.4.3.7.7 [string.copy] p1+2
23.4.3.8.3 [string.substr] p1+2
[2013-10-15: Daniel provides wording]
In addition to the examples mentioned in the discussion, a similar defect exists for thread's join() and detach functions (see 33.4.3.6 [thread.thread.member]). The suggested wording applies a similar fix for these as well.
[2015-05, Lenexa]
STL : likes it
DK : does it change behavior?
Multiple : no
Move to ready? Unanimous
Proposed resolution:
This wording is relative to N3936.
Modify 22.9.2.2 [bitset.cons] as indicated: [Editorial comment: The wording form used to ammend the Throws element is borrowed from a similar style used in 23.4.3.7.6 [string.replace] p10]
template <class charT, class traits, class Allocator> explicit bitset(const basic_string<charT, traits, Allocator>& str, typename basic_string<charT, traits, Allocator>::size_type pos = 0, typename basic_string<charT, traits, Allocator>::size_type n = basic_string<charT, traits, Allocator>::npos, charT zero = charT('0'), charT one = charT('1'));-4- Throws: out_of_range if pos > str.size() or invalid_argument if an invalid character is found (see below). -5- Effects: Determines the effective length rlen of the initializing string as the smaller of n and str.size() - pos. The function then throws invalid_argument if any of the rlen characters in str beginning at position pos is other than zero or one. The function uses traits::eq() to compare the character values. […]
-3- Requires: pos <= str.size().
Modify 22.9.2.3 [bitset.members] as indicated:
bitset<N>& set(size_t pos, bool val = true);-14- Throws: out_of_range if pos does not correspond to a valid bit position. […]
-13- Requires: pos is valid
bitset<N>& reset(size_t pos);-20- Throws: out_of_range if pos does not correspond to a valid bit position. […]
-19- Requires: pos is valid
bitset<N>& flip(size_t pos);-28- Throws: out_of_range if pos does not correspond to a valid bit position. […]
-27- Requires: pos is valid
bool test(size_t pos) const;-42- Throws: out_of_range if pos does not correspond to a valid bit position. […]
-41- Requires: pos is valid
Modify 23.4.3.3 [string.cons] as indicated:
basic_string(const basic_string& str, size_type pos, size_type n = npos, const Allocator& a = Allocator());-4- Throws: out_of_range if pos > str.size().
-3- Requires: pos <= str.size()
Modify 23.4.3.5 [string.capacity] as indicated:
void resize(size_type n, charT c);-7- Throws: length_error if n > max_size().
-6- Requires: n <= max_size()
Modify 23.4.3.7.2 [string.append] as indicated:
basic_string& append(const basic_string& str, size_type pos, size_type n = npos);-4- Throws: out_of_range if pos > str.size().
-3- Requires: pos <= str.size()
Modify 23.4.3.7.3 [string.assign] as indicated:
basic_string& assign(const basic_string& str, size_type pos, size_type n = npos);-6- Throws: out_of_range if pos > str.size().
-5- Requires: pos <= str.size()
Modify 23.4.3.7.4 [string.insert] as indicated: [Editorial note: The first change suggestion is also a bug fix of the current wording, because (a) the function has parameter pos1 but the semantics refers to pos and (b) it is possible that this function can throw length_error, see p10]
basic_string& insert(size_type pos1, const basic_string& str);
-1- Requires: pos <= size().-2- Throws: out_of_range if pos > size().-3- Effects:CallsEquivalent to: return insert(pos, str.data(), str.size());.-4- Returns: *this.
basic_string& insert(size_type pos1, const basic_string& str, size_type pos2, size_type n = npos);-6- Throws: out_of_range if pos1 > size() or pos2 > str.size(). […]
-5- Requires: pos1 <= size() and pos2 <= str.size().
basic_string& insert(size_type pos, const charT* s, size_type n);-9- Requires: s points to an array of at least n elements of charT
-10- Throws: out_of_range if pos > size() or length_error if size() + n > max_size(). […]and pos <= size().
basic_string& insert(size_type pos, const charT* s);-13- Requires:
-14- Effects: Equivalent to return insert(pos, s, traits::length(s));pos <= size() ands points to an array of at least traits::length(s) + 1 elements of charT..-15- Returns: *this.
Modify 23.4.3.7.5 [string.erase] as indicated:
basic_string& erase(size_type pos = 0, size_type n = npos);-2- Throws: out_of_range if pos > size(). […]
-1- Requires: pos <= size()
Modify 23.4.3.7.6 [string.replace] as indicated: [Editorial note: The first change suggestion is also a bug fix of the current wording, because it is possible that this function can throw length_error, see p10]
basic_string& replace(size_type pos1, size_type n1, const basic_string& str);
-1- Requires: pos1 <= size().-2- Throws: out_of_range if pos1 > size().-3- Effects:CallsEquivalent to return replace(pos1, n1, str.data(), str.size());.-4- Returns: *this.
basic_string& replace(size_type pos1, size_type n1, const basic_string& str, size_type pos2, size_type n = npos);-6- Throws: out_of_range if pos1 > size() or pos2 > str.size(). […]
-5- Requires: pos1 <= size() and pos2 <= str.size().
basic_string& replace(size_type pos1, size_type n1, const charT* s, size_type n2);-9- Requires:
-10- Throws: out_of_range if pos1 > size() or length_error if the length of the resulting string would exceed max_size() (see below). […]pos1 <= size() ands points to an array of at least n2 elements of charT.
basic_string& replace(size_type pos, size_type n, const charT* s);-13- Requires:
-14- Effects: Equivalent to return replace(pos, n, s, traits::length(s));pos <= size() ands points to an array of at least traits::length(s) + 1 elements of charT..-15- Returns: *this.
Modify 23.4.3.7.7 [string.copy] as indicated:
size_type copy(charT* s, size_type n, size_type pos = 0) const;-2- Throws: out_of_range if pos > size(). […]
-1- Requires: pos <= size()
Modify 23.4.3.8.3 [string.substr] as indicated:
basic_string substr(size_type pos = 0, size_type n = npos) const;-2- Throws: out_of_range if pos > size(). […]
-1- Requires: pos <= size()
Modify 33.4.3.6 [thread.thread.member] as indicated:
void join();[…] -7- Throws: system_error when an exception is required (30.2.2). -8- Error conditions:
-3- Requires: joinable() is true.
[…]
invalid_argument — if the thread is not joinable.
void detach();[…] -12- Throws: system_error when an exception is required (30.2.2). -13- Error conditions:
-9- Requires: joinable() is true.
[…]
invalid_argument — if the thread is not joinable.