From b136f50d97c097f5491c66ed7357f81d2bbdc995 Mon Sep 17 00:00:00 2001
From: Marshall Clow <marshall@idio.com>
Date: Fri, 15 Nov 2019 14:11:01 -0800
Subject: [PATCH] P1721R2 Mandating the Standard Library: Clause 29 -
 Input/output library

Some minor rewording to avoid bad linebreaks.
---
 source/iostreams.tex | 549 ++++++++++++++-----------------------------
 1 file changed, 177 insertions(+), 372 deletions(-)

diff --git a/source/iostreams.tex b/source/iostreams.tex
index efe3bc8f09..e869e787d0 100644
--- a/source/iostreams.tex
+++ b/source/iostreams.tex
@@ -451,7 +451,7 @@
 as specified in the C standard library.
 
 \pnum
-Concurrent access to a synchronized\iref{ios.members.static} standard iostream object's formatted and unformatted input\iref{istream} and output\iref{ostream} functions or a standard C stream by multiple threads shall not result in a data race\iref{intro.multithread}.
+Concurrent access to a synchronized\iref{ios.members.static} standard iostream object's formatted and unformatted input\iref{istream} and output\iref{ostream} functions or a standard C stream by multiple threads does not result in a data race\iref{intro.multithread}.
 \begin{note}
 Users must still synchronize concurrent use of these objects and streams by multiple threads if they wish to avoid interleaved characters.
 \end{note}
@@ -897,8 +897,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{failure} by constructing the base class with \tcode{msg} and \tcode{ec}.
+Constructs the base class with \tcode{msg} and \tcode{ec}.
 \end{itemdescr}
 
 \indexlibraryctor{ios_base::failure}%
@@ -909,8 +908,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{failure} by constructing the base class with \tcode{msg} and \tcode{ec}.
+Constructs the base class with \tcode{msg} and \tcode{ec}.
 \end{itemdescr}
 
 \rSec4[ios.fmtflags]{Type \tcode{ios_base::fmtflags}}
@@ -1112,8 +1110,6 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{Init}.
 Constructs and initializes the objects \tcode{cin}, \tcode{cout}, \tcode{cerr},
 \tcode{clog}, \tcode{wcin}, \tcode{wcout}, \tcode{wcerr}, and \tcode{wclog} if
 they have not already been constructed and initialized.
@@ -1127,8 +1123,6 @@
 \begin{itemdescr}
 \pnum
 \effects
-Destroys an object of class
-\tcode{Init}.
 If there are no other instances of the class still in existence,
 calls
 \indexlibraryglobal{flush}%
@@ -1296,14 +1290,14 @@
 returns the new locale value
 \tcode{loc}.
 
+\pnum
+\ensures
+\tcode{loc == getloc()}.
+
 \pnum
 \returns
 The previous value of
 \tcode{getloc()}.
-
-\pnum
-\ensures
-\tcode{loc == getloc()}.
 \end{itemdescr}
 
 \indexlibrarymember{getloc}{ios_base}%
@@ -1397,7 +1391,7 @@
 
 \pnum
 \remarks
-Concurrent access to this function by multiple threads shall not result in a data
+Concurrent access to this function by multiple threads does not result in a data
 race\iref{intro.multithread}.
 \end{itemdescr}
 
@@ -1408,7 +1402,7 @@
 
 \begin{itemdescr}
 \pnum
-\requires
+\expects
 \tcode{idx} is a value obtained by a call to \tcode{xalloc}.
 
 \pnum
@@ -1458,7 +1452,7 @@
 
 \begin{itemdescr}
 \pnum
-\requires
+\expects
 \tcode{idx} is a value obtained by a call to \tcode{xalloc}.
 
 \pnum
@@ -1513,6 +1507,12 @@
 \end{itemdecl}
 
 \begin{itemdescr}
+\pnum
+\expects
+The function
+\tcode{fn}
+does not throw exceptions.
+
 \pnum
 \effects
 Registers the pair
@@ -1530,12 +1530,6 @@
 registration.
 Functions registered while a callback function is active are not called until the next event.
 
-\pnum
-\requires
-The function
-\tcode{fn}
-shall not throw exceptions.
-
 \pnum
 \remarks
 Identical pairs are not merged.
@@ -1569,8 +1563,6 @@
 \begin{itemdescr}
 \pnum
 \effects
-Destroys an object of class
-\tcode{ios_base}.
 Calls each registered callback pair
 \tcode{(fn, idx)}\iref{ios.base.callback} as
 \tcode{(*fn)(\brk{}erase_event, *this, idx)}
@@ -1816,9 +1808,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_ios},
-assigning initial values to its member objects by calling
+Assigns initial values to its member objects by calling
 \tcode{init(sb)}.
 \end{itemdescr}
 
@@ -1830,9 +1820,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_ios}\iref{ios.base.cons}
-leaving its member objects uninitialized. The object
+Leaves its member objects uninitialized. The object
 shall be initialized by calling
 \tcode{basic_ios::init}
 before its first use or before it is destroyed, whichever comes first; otherwise the
@@ -1909,8 +1897,8 @@
 
 \begin{itemdescr}
 \pnum
-\requires
-If \tcode{tiestr} is not null, \tcode{tiestr} shall not be reachable by
+\expects
+If \tcode{tiestr} is not null, \tcode{tiestr} is not reachable by
 traversing the linked list of tied stream objects starting from
 \tcode{tiestr->tie()}.
 
@@ -1943,15 +1931,15 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\ensures
-\tcode{sb == rdbuf()}.
-
 \pnum
 \effects
 Calls
 \tcode{clear()}.
 
+\pnum
+\ensures
+\tcode{sb == rdbuf()}.
+
 \pnum
 \returns
 The previous value of
@@ -2039,7 +2027,7 @@
 \pnum
 \effects
 If
-\tcode{(this == addressof(rhs))}
+\tcode{(this == addressof(rhs))} is \tcode{true}
 does nothing.
 Otherwise assigns to the member objects of
 \tcode{*this}
@@ -2070,7 +2058,6 @@
 \tcode{(*fn)(copyfmt_event, *this, idx)};
 
 \item then, calls \tcode{exceptions(rhs.exceptions())}.
-
 \end{itemize}
 
 \pnum
@@ -2120,12 +2107,12 @@
 \begin{itemdescr}
 \pnum
 \ensures
-\tcode{*this} shall have the state that
+\tcode{*this} has the state that
 \tcode{rhs} had before the function call, except that
-\tcode{rdbuf()} shall return 0. \tcode{rhs} shall be in a valid but
-unspecified state, except that \tcode{rhs.rdbuf()} shall return the
+\tcode{rdbuf()} returns \tcode{nullptr}. \tcode{rhs} is in a valid but
+unspecified state, except that \tcode{rhs.rdbuf()} returns the
 same value as it returned before the function call, and
-\tcode{rhs.tie()} shall return 0.
+\tcode{rhs.tie()} returns \tcode{nullptr}.
 \end{itemdescr}
 
 \indexlibrarymember{swap}{basic_ios}%
@@ -2137,9 +2124,9 @@
 \pnum
 \effects
 The states of \tcode{*this} and \tcode{rhs}
-shall be exchanged, except that \tcode{rdbuf()} shall return the same
+are exchanged, except that \tcode{rdbuf()} returns the same
 value as it returned before the function call, and \tcode{rhs.rdbuf()}
-shall return the same value as it returned before the function call.
+returns the same value as it returned before the function call.
 \end{itemdescr}
 
 \indexlibrarymember{set_rdbuf}{basic_ios}%
@@ -2149,7 +2136,8 @@
 
 \begin{itemdescr}
 \pnum
-\requires \tcode{sb != nullptr}.
+\expects
+\tcode{sb != nullptr} is \tcode{true}.
 
 \pnum
 \effects
@@ -2159,7 +2147,7 @@
 
 \pnum
 \ensures
-\tcode{rdbuf() == sb}.
+\tcode{rdbuf() == sb} is \tcode{true}.
 
 \pnum
 \throws
@@ -3044,9 +3032,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_streambuf<charT, traits>}
-and initializes:\footnote{The default constructor is protected for class
+Initializes:\footnote{The default constructor is protected for class
 \tcode{basic_streambuf}
 to assure that only objects for classes
 derived from this class may be constructed.}
@@ -3078,13 +3064,8 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Constructs a copy of \tcode{rhs}.
-
 \pnum
 \ensures
-
 \begin{itemize}
 \item \tcode{eback() == rhs.eback()}
 \item \tcode{gptr() == rhs.gptr()}
@@ -3117,15 +3098,15 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\ensures
-\tcode{loc == getloc()}.
-
 \pnum
 \effects
 Calls
 \tcode{imbue(loc)}.
 
+\pnum
+\ensures
+\tcode{loc == getloc()}.
+
 \pnum
 \returns
 Previous value of
@@ -3249,7 +3230,7 @@
 
 \begin{itemdescr}
 \pnum
-\returns
+\effects
 If the input sequence read position is not available,
 returns
 \tcode{uflow()}.
@@ -3293,7 +3274,7 @@
 
 \begin{itemdescr}
 \pnum
-\returns
+\effects
 If the input sequence putback position is not available, or
 if
 \tcode{traits::eq(c, gptr()[-1])}
@@ -3311,7 +3292,7 @@
 
 \begin{itemdescr}
 \pnum
-\returns
+\effects
 If the input sequence putback position is not available,
 returns
 \tcode{pbackfail()}.
@@ -3329,7 +3310,7 @@
 
 \begin{itemdescr}
 \pnum
-\returns
+\effects
 If the output sequence write position is not available,
 returns
 \tcode{overflow(traits::to_int_type(c))}.
@@ -3360,14 +3341,8 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Assigns the data members of \tcode{rhs}
-to \tcode{*this}.
-
 \pnum
 \ensures
-
 \begin{itemize}
 \item \tcode{eback() == rhs.eback()}
 \item \tcode{gptr() == rhs.gptr()}
@@ -3452,7 +3427,7 @@
 \tcode{gbeg == eback()},
 \tcode{gnext == gptr()},
 and
-\tcode{gend == egptr()}.
+\tcode{gend == egptr()} are all \tcode{true}.
 \end{itemdescr}
 
 \rSec4[streambuf.put.area]{Put area access}
@@ -3512,7 +3487,7 @@
 \tcode{pbeg == pbase()},
 \tcode{pbeg == pptr()},
 and
-\tcode{pend == epptr()}.
+\tcode{pend == epptr()} are all \tcode{true}.
 \end{itemdescr}
 
 \rSec3[streambuf.virtuals]{Virtual functions}
@@ -3823,12 +3798,11 @@
 
 \begin{itemdescr}
 \pnum
-\requires
+\expects
 The constraints are the same as for
 \tcode{underflow()},
-except that the result character shall be transferred from the pending
-sequence to the backup sequence, and the pending sequence shall not
-be empty before the transfer.
+except that the result character is transferred from the pending
+sequence to the backup sequence, and the pending sequence is not empty before the transfer.
 
 \pnum
 \default
@@ -3984,9 +3958,9 @@
 argument character sequence.
 
 \pnum
-\requires
+\expects
 Every overriding definition of this virtual function
-shall obey the following constraints:
+obeys the following constraints:
 \begin{itemize}
 \item
 The effect of consuming a character on the associated output sequence is
@@ -4006,7 +3980,7 @@
 \tcode{pbase()}
 and
 \tcode{pptr()}
-shall be set so that:
+are set so that:
 \tcode{pptr() - pbase() == r}
 and the \tcode{r} characters starting at
 \tcode{pbase()}
@@ -4324,8 +4298,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_istream}, initializing the base class subobject with
+Initializes the base class subobject with
 \tcode{basic_ios::init(sb)}\iref{basic.ios.cons}.
 
 \pnum
@@ -4342,11 +4315,10 @@
 \begin{itemdescr}
 \pnum
 \effects
-Move constructs from the rvalue \tcode{rhs}.
-This is accomplished by default constructing the base class, copying the
-\tcode{gcount()} from \tcode{rhs}, calling
+Default constructs the base class, copies the
+\tcode{gcount()} from \tcode{rhs}, calls
 \tcode{basic_ios<charT, traits>::move(rhs)} to initialize the base
-class, and setting the \tcode{gcount()} for \tcode{rhs} to 0.
+class, and sets the \tcode{gcount()} for \tcode{rhs} to 0.
 \end{itemdescr}
 
 \indexlibrarydtor{basic_istream}%
@@ -4355,11 +4327,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Destroys an object of class
-\tcode{basic_istream}.
-
 \pnum
 \remarks
 Does not perform any operations of
@@ -4376,7 +4343,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{swap(rhs)}.
+Equivalent to: \tcode{swap(rhs)}.
 
 \pnum
 \returns
@@ -4535,8 +4502,7 @@
 
 \begin{itemdescr}
 \pnum
-\effects
-Returns
+\returns
 \tcode{ok_}.
 \end{itemdescr}
 
@@ -5587,6 +5553,9 @@
 \end{itemdecl}
 
 \begin{itemdescr}
+\pnum
+\constraints The expression \tcode{is >> std::forward<T>(x)} is well-formed when treated as an unevaluated operand.
+
 \pnum
 \effects
 Equivalent to:
@@ -5594,11 +5563,6 @@
 is >> std::forward<T>(x);
 return is;
 \end{codeblock}
-
-\pnum
-\remarks
-This function shall not participate in overload resolution
-unless the expression \tcode{is >> std::forward<T>(x)} is well-formed.
 \end{itemdescr}
 
 \rSec3[iostreamclass]{Class template \tcode{basic_iostream}}
@@ -5686,11 +5650,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Destroys an object of class
-\tcode{basic_iostream}.
-
 \pnum
 \remarks
 Does not perform any operations on
@@ -5707,7 +5666,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{swap(rhs)}.
+Equivalent to: \tcode{swap(rhs)}.
 \end{itemdescr}
 
 \indexlibrarymember{swap}{basic_iostream}%
@@ -5955,11 +5914,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Destroys an object of class
-\tcode{basic_ostream}.
-
 \pnum
 \remarks
 Does not perform any operations on
@@ -5976,7 +5930,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{swap(rhs)}.
+Equivalent to: \tcode{swap(rhs)}.
 
 \pnum
 \returns
@@ -6519,8 +6473,8 @@
 
 \begin{itemdescr}
 \pnum
-\requires
-\tcode{s} shall not be a null pointer.
+\expects
+\tcode{s} is not a null pointer.
 
 \pnum
 \effects
@@ -6811,6 +6765,9 @@
 \end{itemdecl}
 
 \begin{itemdescr}
+\pnum
+\constraints The expression \tcode{os << x} is well-formed when treated as an unevaluated operand.
+
 \pnum
 \effects
 As if by: \tcode{os << x;}
@@ -6818,11 +6775,6 @@
 \pnum
 \returns
 \tcode{os}.
-
-\pnum
-\remarks
-This function shall not participate in overload resolution
-unless the expression \tcode{os << x} is well-formed.
 \end{itemdescr}
 
 
@@ -6864,10 +6816,11 @@
 }
 \end{codeblock}
 
-The expression \tcode{out << resetiosflags(mask)} shall have
+The expression \tcode{out << resetiosflags(mask)} has
 type \tcode{basic_ostream<charT, traits>\&} and value \tcode{out}. The
-expression \tcode{in >> resetiosflags(mask)} shall have type
-\tcode{basic_istream<charT, traits>\&} and value \tcode{in}. \end{itemdescr}
+expression \tcode{in >> resetiosflags(mask)} has type
+\tcode{basic_istream<charT, traits>\&} and value \tcode{in}.
+\end{itemdescr}
 
 \indexlibraryglobal{setiosflags}%
 \begin{itemdecl}
@@ -6904,14 +6857,14 @@
 
 The expression
 \tcode{out << setiosflags(mask)}
-shall have type
+has type
 \tcode{basic_ostream<charT, traits>\&}
 and value
 \tcode{out}.
 The expression
 \tcode{in >> setiosflags(mask)}
-shall have type
-\tcode{basic_istream<charT, \\traits>\&}
+has type
+\tcode{basic_istream<charT, traits>\&}
 and value
 \tcode{in}.
 \end{itemdescr}
@@ -6953,13 +6906,13 @@
 
 The expression
 \tcode{out << setbase(base)}
-shall have type
+has type
 \tcode{basic_ostream<charT, traits>\&}
 and value
 \tcode{out}.
 The expression
 \tcode{in >> setbase(base)}
-shall have type
+has type
 \tcode{basic_istream<charT, traits>\&}
 and value
 \tcode{in}.
@@ -6994,7 +6947,7 @@
 
 The expression
 \tcode{out << setfill(c)}
-shall have type
+has type
 \tcode{basic_ostream<charT, traits>\&}
 and value
 \tcode{out}.
@@ -7034,13 +6987,13 @@
 
 The expression
 \tcode{out << setprecision(n)}
-shall have type
+has type
 \tcode{basic_ostream<charT, traits>\&}
 and value
 \tcode{out}.
 The expression
 \tcode{in >> setprecision(n)}
-shall have type
+has type
 \tcode{basic_istream<charT, traits>\&}
 and value
 \tcode{in}.
@@ -7080,13 +7033,13 @@
 
 The expression
 \tcode{out << setw(n)}
-shall have type
+has type
 \tcode{basic_ostream<charT, traits>\&}
 and value
 \tcode{out}.
 The expression
 \tcode{in >> setw(n)}
-shall have type
+has type
 \tcode{basic_istream<charT, traits>\&}
 and value
 \tcode{in}.
@@ -7105,8 +7058,9 @@
 
 \begin{itemdescr}
 \pnum
-\requires The type \tcode{moneyT} shall be either \tcode{long double} or a
-specialization of the \tcode{basic_string} template\iref{strings}.
+\mandates
+The type \tcode{moneyT} is either \tcode{long double} or
+a specialization of the \tcode{basic_string} template\iref{strings}.
 
 \pnum
 \effects
@@ -7136,7 +7090,7 @@
 }
 \end{codeblock}
 
-The expression \tcode{in >> get_money(mon, intl)} shall have type
+The expression \tcode{in >> get_money(mon, intl)} has type
 \tcode{basic_istream<charT, traits>\&} and value \tcode{in}.
 \end{itemdescr}
 
@@ -7147,8 +7101,9 @@
 
 \begin{itemdescr}
 \pnum
-\requires The type \tcode{moneyT} shall be either \tcode{long double} or a
-specialization of the \tcode{basic_string} template\iref{strings}.
+\mandates
+The type \tcode{moneyT} is either \tcode{long double} or
+a specialization of the \tcode{basic_string} template\iref{strings}.
 
 \pnum
 \returns
@@ -7172,9 +7127,8 @@
 }
 \end{codeblock}
 
-The expression \tcode{out << put_money(mon, intl)} shall have type
+The expression \tcode{out << put_money(mon, intl)} has type
 \tcode{basic_ostream<charT, traits>\&} and value \tcode{out}.
-
 \end{itemdescr}
 
 \indexlibraryglobal{get_time}%
@@ -7184,8 +7138,9 @@
 
 \begin{itemdescr}
 \pnum
-\requires The argument \tcode{tmb} shall be a valid pointer to an object of type \tcode{struct tm}.
-The argument \tcode{fmt} shall be a valid pointer to an array of objects of type \tcode{charT} with \tcode{char_traits<charT>::length(fmt)} elements.
+\expects
+The argument \tcode{tmb} is a valid pointer to an object of type \tcode{struct tm},
+and \range{fmt}{fmt + char_traits<charT>::length(fmt)} is a valid range.
 
 \pnum
 \returns
@@ -7211,7 +7166,7 @@
 }
 \end{codeblock}
 
-The expression \tcode{in >> get_time(tmb, fmt)} shall have type
+The expression \tcode{in >> get_time(tmb, fmt)} has type
 \tcode{basic_istream<charT, traits>\&} and value \tcode{in}.
 \end{itemdescr}
 
@@ -7222,10 +7177,9 @@
 
 \begin{itemdescr}
 \pnum
-\requires The argument \tcode{tmb} shall be a valid pointer to an object of type
-\tcode{struct tm}, and the argument \tcode{fmt} shall be a valid pointer to an
-array of objects of type \tcode{charT} with
-\tcode{char_traits<charT>::length(\brk{}fmt)} elements.
+\expects
+The argument \tcode{tmb} is a valid pointer to an object of type \tcode{struct tm},
+and \range{fmt}{fmt + char_traits<charT>::length(fmt)} is a valid range.
 
 \pnum
 \returns
@@ -7249,7 +7203,7 @@
 }
 \end{codeblock}
 
-The expression \tcode{out << put_time(tmb, fmt)} shall have type
+The expression \tcode{out << put_time(tmb, fmt)} has type
 \tcode{basic_ostream<charT, traits>\&} and value \tcode{out}.
 \end{itemdescr}
 
@@ -7295,7 +7249,7 @@
 in~\ref{ostream.formatted.reqmts}, \tcode{seq} is inserted as if by calling
 \tcode{out.rdbuf()->sputn(seq, n)}, where \tcode{n} is the larger of
 \tcode{out.width()} and \tcode{x}, and \tcode{out.width(0)} is called.
-The expression \tcode{out << quoted(s, delim, escape)} shall have type
+The expression \tcode{out << quoted(s, delim, escape)} has type
 \tcode{basic_ostream<charT, traits>\&} and value \tcode{out}.
 \end{itemdescr}
 
@@ -7339,11 +7293,13 @@
 \tcode{out << quoted(s, delim, escape)} behaves as specified for the
 \tcode{const basic_string<charT, traits, Allocator>\&} overload of the
 \tcode{quoted} function.
-\end{itemize}
-The expression \tcode{in >> quoted(s, delim, escape)} shall have type
-\tcode{basic_istream<charT, traits>\&} and value \tcode{in}. The expression
-\tcode{out << quoted(s, delim, escape)} shall have type
+\item
+The expression \tcode{in >> quoted(s, delim, escape)} has type
+\tcode{basic_istream<charT, traits>\&} and value \tcode{in}.
+\item
+The expression \tcode{out << quoted(s, delim, escape)} has type
 \tcode{basic_ostream\brk{}<charT, traits>\&} and value \tcode{out}.
+\end{itemize}
 \end{itemdescr}
 
 \rSec1[string.streams]{String-based streams}
@@ -7735,7 +7691,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{x.swap(y)}.
+Equivalent to: \tcode{x.swap(y)}.
 \end{itemdescr}
 
 \rSec3[stringbuf.members]{Member functions}
@@ -8396,29 +8352,12 @@
 Move constructs from the rvalue \tcode{rhs}. This
 is accomplished by move constructing the base class, and the contained
 \tcode{basic_stringbuf}.
-Next \tcode{basic_istream<charT, traits>::set_rdbuf(addressof(sb))}
-is called to
-install the contained \tcode{basic_stringbuf}.
+Then calls \tcode{basic_istream<charT, traits>::set_rdbuf(addressof(sb))}
+to install the contained \tcode{basic_stringbuf}.
 \end{itemdescr}
 
 \rSec3[istringstream.assign]{Assignment and swap}
 
-\indexlibrarymember{operator=}{basic_istringstream}%
-\begin{itemdecl}
-basic_istringstream& operator=(basic_istringstream&& rhs);
-\end{itemdecl}
-
-\begin{itemdescr}
-\pnum
-\effects
-Move assigns the base and members of \tcode{*this} from the base and corresponding
-members of \tcode{rhs}.
-
-\pnum
-\returns
-\tcode{*this}.
-\end{itemdescr}
-
 \indexlibrarymember{swap}{basic_istringstream}%
 \begin{itemdecl}
 void swap(basic_istringstream& rhs);
@@ -8445,7 +8384,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{x.swap(y)}.
+Equivalent to: \tcode{x.swap(y)}.
 \end{itemdescr}
 
 \rSec3[istringstream.members]{Member functions}
@@ -8733,29 +8672,12 @@
 Move constructs from the rvalue \tcode{rhs}. This
 is accomplished by move constructing the base class, and the contained
 \tcode{basic_stringbuf}.
-Next \tcode{basic_ostream<charT, traits>::set_rdbuf(addressof(sb))}
-is called to
-install the contained \tcode{basic_stringbuf}.
+Then calls \tcode{basic_ostream<charT, traits>::set_rdbuf(addressof(sb))}
+to install the contained \tcode{basic_stringbuf}.
 \end{itemdescr}
 
 \rSec3[ostringstream.assign]{Assignment and swap}
 
-\indexlibrarymember{operator=}{basic_ostringstream}%
-\begin{itemdecl}
-basic_ostringstream& operator=(basic_ostringstream&& rhs);
-\end{itemdecl}
-
-\begin{itemdescr}
-\pnum
-\effects
-Move assigns the base and members of \tcode{*this} from the base and corresponding
-members of \tcode{rhs}.
-
-\pnum
-\returns
-\tcode{*this}.
-\end{itemdescr}
-
 \indexlibrarymember{swap}{basic_ostringstream}%
 \begin{itemdecl}
 void swap(basic_ostringstream& rhs);
@@ -8781,7 +8703,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{x.swap(y)}.
+Equivalent to: \tcode{x.swap(y)}.
 \end{itemdescr}
 
 \rSec3[ostringstream.members]{Member functions}
@@ -9075,28 +8997,12 @@
 Move constructs from the rvalue \tcode{rhs}. This
 is accomplished by move constructing the base class, and the contained
 \tcode{basic_stringbuf}.
-Next \tcode{basic_istream<charT, traits>::set_rdbuf(addressof(sb))} is called to
-install the contained \tcode{basic_stringbuf}.
+Then calls \tcode{basic_istream<charT, traits>::set_rdbuf(addressof(sb))}
+to install the contained \tcode{basic_stringbuf}.
 \end{itemdescr}
 
 \rSec3[stringstream.assign]{Assignment and swap}
 
-\indexlibrarymember{operator=}{basic_stringstream}%
-\begin{itemdecl}
-basic_stringstream& operator=(basic_stringstream&& rhs);
-\end{itemdecl}
-
-\begin{itemdescr}
-\pnum
-\effects
-Move assigns the base and members of \tcode{*this} from the base and corresponding
-members of \tcode{rhs}.
-
-\pnum
-\returns
-\tcode{*this}.
-\end{itemdescr}
-
 \indexlibrarymember{swap}{basic_stringstream}%
 \begin{itemdecl}
 void swap(basic_stringstream& rhs);
@@ -9122,7 +9028,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{x.swap(y)}.
+Equivalent to: \tcode{x.swap(y)}.
 \end{itemdescr}
 
 \rSec3[stringstream.members]{Member functions}
@@ -9400,9 +9306,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_filebuf<charT, traits>},
-initializing the base class with
+Initializes the base class with
 \tcode{basic_streambuf<charT, traits>()}\iref{streambuf.cons}.
 
 \pnum
@@ -9418,8 +9322,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Move constructs from the rvalue \tcode{rhs}. It
-is \impldef{whether sequence pointers are copied by \tcode{basic_filebuf} move
+It is \impldef{whether sequence pointers are copied by \tcode{basic_filebuf} move
 constructor} whether the sequence pointers in \tcode{*this}
 (\tcode{eback()}, \tcode{gptr()}, \tcode{egptr()},
 \tcode{pbase()}, \tcode{pptr()}, \tcode{epptr()}) obtain
@@ -9461,8 +9364,6 @@
 \begin{itemdescr}
 \pnum
 \effects
-Destroys an object of class
-\tcode{basic_filebuf<charT, traits>}.
 Calls
 \tcode{close()}.
 If an exception occurs during the destruction of the object, including the call to \tcode{close()}, the exception is caught but not rethrown (see~\ref{res.on.exception.handling}).
@@ -9509,7 +9410,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{x.swap(y)}.
+Equivalent to: \tcode{x.swap(y)}.
 \end{itemdescr}
 
 \rSec3[filebuf.members]{Member functions}
@@ -9539,7 +9440,7 @@
 \begin{itemdescr}
 \pnum
 \expects
-\tcode{s} shall point to a NTCTS\iref{defns.ntcts}.
+\tcode{s} points to a NTCTS\iref{defns.ntcts}.
 
 \pnum
 \effects
@@ -10034,7 +9935,7 @@
 
 \begin{itemdescr}
 \pnum
-\requires
+\expects
 If the file is not positioned at its beginning and the encoding of the current
 locale as determined by
 \tcode{a_codecvt.encoding()}
@@ -10131,11 +10032,9 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_ifstream<charT, traits>},
-initializing the base class with
+Initializes the base class with
 \tcode{basic_istream<charT, traits>(addressof(sb))}\iref{istream.cons}
-and initializing \tcode{sb} with
+and \tcode{sb} with
 \tcode{basic_filebuf<charT, traits>()}\iref{filebuf.cons}.
 \end{itemdescr}
 
@@ -10150,11 +10049,9 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_ifstream<charT, traits>},
-initializing the base class with
+Initializes the base class with
 \tcode{basic_istream<charT, traits>(addressof(sb))}\iref{istream.cons}
-and initializing \tcode{sb} with
+and \tcode{sb} with
 \tcode{basic_filebuf<charT, traits>()}\iref{filebuf.cons},
 then calls
 \tcode{rdbuf()->open(s, mode | ios_base::in)}.
@@ -10173,7 +10070,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-The same as \tcode{basic_ifstream(s.c_str(), mode)}.
+Equivalent to: \tcode{basic_ifstream(s.c_str(), mode)}.
 \end{itemdescr}
 
 \indexlibraryctor{basic_ifstream}%
@@ -10184,32 +10081,13 @@
 \begin{itemdescr}
 \pnum
 \effects
-Move constructs from the rvalue \tcode{rhs}. This
-is accomplished by move constructing the base class, and the contained
-\tcode{basic_filebuf}. Next
-\tcode{basic_istream<charT, traits>::set_rdbuf(\brk{}addressof(sb))}
-is called to install
-the contained \tcode{basic_filebuf}.
+Move constructs the base class, and the contained \tcode{basic_filebuf}.
+Then calls \tcode{basic_istream<charT, traits>::set_rdbuf(\brk{}addressof(sb))}
+to install the contained \tcode{basic_filebuf}.
 \end{itemdescr}
 
 \rSec3[ifstream.assign]{Assignment and swap}
 
-\indexlibrarymember{operator=}{basic_ifstream}%
-\begin{itemdecl}
-basic_ifstream& operator=(basic_ifstream&& rhs);
-\end{itemdecl}
-
-\begin{itemdescr}
-\pnum
-\effects
-Move assigns the base and members of \tcode{*this} from the base and corresponding
-members of \tcode{rhs}.
-
-\pnum
-\returns
-\tcode{*this}.
-\end{itemdescr}
-
 \indexlibrarymember{swap}{basic_ifstream}%
 \begin{itemdecl}
 void swap(basic_ifstream& rhs);
@@ -10234,7 +10112,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{x.swap(y)}.
+Equivalent to: \tcode{x.swap(y)}.
 \end{itemdescr}
 
 \rSec3[ifstream.members]{Member functions}
@@ -10387,11 +10265,9 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_ofstream<charT, traits>},
-initializing the base class with
+Initializes the base class with
 \tcode{basic_ostream<charT, traits>(addressof(sb))}\iref{ostream.cons}
-and initializing \tcode{sb} with
+and \tcode{sb} with
 \tcode{basic_filebuf<charT, traits>()}\iref{filebuf.cons}.
 \end{itemdescr}
 
@@ -10406,11 +10282,9 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_ofstream<charT, traits>},
-initializing the base class with
+Initializes the base class with
 \tcode{basic_ostream<charT, traits>(addressof(sb))}\iref{ostream.cons}
-and initializing \tcode{sb} with
+and \tcode{sb} with
 \tcode{basic_filebuf<charT, traits>()}\iref{filebuf.cons},
 then calls
 \tcode{rdbuf()->open(s, mode | ios_base::out)}.
@@ -10429,7 +10303,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-The same as \tcode{basic_ofstream(s.c_str(), mode)}.
+Equivalent to: \tcode{basic_ofstream(s.c_str(), mode)}.
 \end{itemdescr}
 
 \indexlibraryctor{basic_ofstream}%
@@ -10440,32 +10314,13 @@
 \begin{itemdescr}
 \pnum
 \effects
-Move constructs from the rvalue \tcode{rhs}. This
-is accomplished by move constructing the base class, and the contained
-\tcode{basic_filebuf}. Next
-\tcode{basic_ostream<charT, traits>::set_rdbuf(\brk{}addressof(sb))}
-is called to install
-the contained \tcode{basic_filebuf}.
+Move constructs the base class, and the contained \tcode{basic_filebuf}.
+Then calls \tcode{basic_ostream<charT, traits>::set_rdbuf(\brk{}addressof(sb))}
+to install the contained \tcode{basic_filebuf}.
 \end{itemdescr}
 
 \rSec3[ofstream.assign]{Assignment and swap}
 
-\indexlibrarymember{operator=}{basic_ofstream}%
-\begin{itemdecl}
-basic_ofstream& operator=(basic_ofstream&& rhs);
-\end{itemdecl}
-
-\begin{itemdescr}
-\pnum
-\effects
-Move assigns the base and members of \tcode{*this} from the base and corresponding
-members of \tcode{rhs}.
-
-\pnum
-\returns
-\tcode{*this}.
-\end{itemdescr}
-
 \indexlibrarymember{swap}{basic_ofstream}%
 \begin{itemdecl}
 void swap(basic_ofstream& rhs);
@@ -10490,7 +10345,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{x.swap(y)}.
+Equivalent to: \tcode{x.swap(y)}.
 \end{itemdescr}
 
 \rSec3[ofstream.members]{Member functions}
@@ -10652,14 +10507,10 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_fstream<charT, traits>},
-initializing the base class with
+Initializes the base class with
 \tcode{basic_iostream<charT, traits>(addressof(sb))}\iref{iostream.cons}
-and initializing
-\tcode{sb}
-with
-\tcode{basic_filebuf<charT, traits>()}.
+and
+\tcode{sb} with \tcode{basic_filebuf<charT, traits>()}.
 \end{itemdescr}
 
 \indexlibraryctor{basic_fstream}%
@@ -10675,14 +10526,10 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an object of class
-\tcode{basic_fstream<charT, traits>},
-initializing the base class with
+Initializes the base class with
 \tcode{basic_iostream<charT, traits>(addressof(sb))}\iref{iostream.cons}
-and initializing
-\tcode{sb}
-with
-\tcode{basic_filebuf<charT, traits>()}.
+and
+\tcode{sb} with \tcode{basic_filebuf<charT, traits>()}.
 Then calls
 \tcode{rdbuf()->open(s, mode)}.
 If that function returns a null pointer, calls
@@ -10702,7 +10549,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-The same as \tcode{basic_fstream(s.c_str(), mode)}.
+Equivalent to: \tcode{basic_fstream(s.c_str(), mode)}.
 \end{itemdescr}
 
 \indexlibraryctor{basic_fstream}%
@@ -10713,32 +10560,13 @@
 \begin{itemdescr}
 \pnum
 \effects
-Move constructs from the rvalue \tcode{rhs}. This
-is accomplished by move constructing the base class, and the contained
-\tcode{basic_filebuf}. Next
-\tcode{basic_istream<charT, traits>::set_rdbuf(\brk{}addressof(sb))}
-is called to install
-the contained \tcode{basic_filebuf}.
+Move constructs the base class, and the contained \tcode{basic_filebuf}.
+Then calls \tcode{basic_istream<charT, traits>::set_rdbuf(\brk{}addressof(sb))}
+to install the contained \tcode{basic_filebuf}.
 \end{itemdescr}
 
 \rSec3[fstream.assign]{Assignment and swap}
 
-\indexlibrarymember{operator=}{basic_fstream}%
-\begin{itemdecl}
-basic_fstream& operator=(basic_fstream&& rhs);
-\end{itemdecl}
-
-\begin{itemdescr}
-\pnum
-\effects
-Move assigns the base and members of \tcode{*this} from the base and corresponding
-members of \tcode{rhs}.
-
-\pnum
-\returns
-\tcode{*this}.
-\end{itemdescr}
-
 \indexlibrarymember{swap}{basic_fstream}%
 \begin{itemdecl}
 void swap(basic_fstream& rhs);
@@ -10763,7 +10591,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-As if by \tcode{x.swap(y)}.
+Equivalent to: \tcode{x.swap(y)}.
 \end{itemdescr}
 
 \rSec3[fstream.members]{Member functions}
@@ -10953,8 +10781,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs the \tcode{basic_syncbuf} object and
-sets \tcode{wrapped} to \tcode{obuf}.
+Sets \tcode{wrapped} to \tcode{obuf}.
 
 \pnum
 \remarks
@@ -10980,10 +10807,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Move constructs from \tcode{other} (\tref{cpp17.moveconstructible}).
-
 \pnum
 \ensures
 The value returned by \tcode{this->get_wrapped()}
@@ -11068,7 +10891,7 @@
 
 \begin{itemdescr}
 \pnum
-\requires
+\expects
 Either
 \tcode{allocator_traits<Allocator>::propagate_on_container_swap::value}
 is \tcode{true}
@@ -11556,7 +11379,8 @@
 \pnum
 If the possibility of a file system race would make it unreliable for a
 program to test for a precondition before calling a function described herein,
-\requires is not specified for the function.
+% {} on next line suppresses a check failure for a missing newline after \expects.
+{}\expects is not specified for the function.
 \begin{note}
 As a design practice, preconditions are not specified when it
 is unreasonable for a program to detect them prior to calling the function.
@@ -12439,10 +12263,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Constructs an object of class \tcode{path}.
-
 \pnum
 \ensures
 \tcode{empty() == true}.
@@ -12506,7 +12326,7 @@
 
 \begin{itemdescr}
 \pnum
-\requires
+\mandates
 The value type of \tcode{Source} and \tcode{InputIterator} is
 \tcode{char}.
 
@@ -12849,14 +12669,14 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\ensures
-\tcode{!has_filename()}.
-
 \pnum
 \effects
 Remove the generic format pathname of \tcode{filename()} from the generic format pathname.
 
+\pnum
+\ensures
+\tcode{!has_filename()}.
+
 \pnum
 \returns
 \tcode{*this}.
@@ -14859,10 +14679,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Constructs an object of class \tcode{directory_iterator}.
-
 \pnum
 \ensures
 \tcode{*this} has the original value of \tcode{rhs}.
@@ -14897,7 +14713,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-
 \pnum
 \effects
 As specified for the prefix increment operation of
@@ -14910,7 +14725,6 @@
 \pnum
 \throws
 As specified in~\ref{fs.err.report}.
-
 \end{itemdescr}
 
 \rSec3[fs.dir.itr.nonmembers]{Non-member functions}
@@ -15019,14 +14833,11 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-
 \pnum
 \effects
 Constructs the end iterator.
-
 \end{itemdescr}
 
-
 \indexlibraryctor{recursive_directory_iterator}%
 \begin{itemdecl}
 explicit recursive_directory_iterator(const path& p);
@@ -15036,7 +14847,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-
 \pnum
 \effects
 Constructs an iterator representing the first
@@ -15078,10 +14888,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Constructs an object of class \tcode{recursive_directory_iterator}.
-
 \pnum
 \ensures
 \begin{itemize}
@@ -15097,10 +14903,6 @@
 \end{itemdecl}
 
 \begin{itemdescr}
-\pnum
-\effects
-Constructs an object of class \tcode{recursive_directory_iterator}.
-
 \pnum
 \ensures
 \tcode{options()}, \tcode{depth()},
@@ -15450,8 +15252,9 @@
 
 \begin{itemdescr}
 \pnum
-\requires At most one element from each option group\iref{fs.enum.copy.opts}
-  is set in \tcode{options}.
+\expects
+At most one element from each option group\iref{fs.enum.copy.opts}
+is set in \tcode{options}.
 
 \pnum
 \effects
@@ -15596,7 +15399,6 @@
     file3
 \end{codeblock}
 \end{example}
-
 \end{itemdescr}
 
 
@@ -15617,7 +15419,6 @@
 \pnum
 \throws
 As specified in~\ref{fs.err.report}.
-
 \end{itemdescr}
 
 \indexlibraryglobal{copy_file}%
@@ -15629,9 +15430,10 @@
 
 \begin{itemdescr}
 \pnum
-\requires At most one element from each
-  option group\iref{fs.enum.copy.opts} is set
-  in \tcode{options}.
+\expects
+At most one element from each
+option group\iref{fs.enum.copy.opts} is set
+in \tcode{options}.
 
 \pnum
 \effects
@@ -16469,24 +16271,27 @@
 
 \begin{itemdescr}
 \pnum
-  \requires Exactly one of the \tcode{perm_options} constants
-  \tcode{replace}, \tcode{add}, or \tcode{remove} is present in \tcode{opts}.
+\expects
+Exactly one of the \tcode{perm_options} constants
+\tcode{replace}, \tcode{add}, or \tcode{remove} is present in \tcode{opts}.
 
 \pnum
-  \remarks The second signature behaves as if it had an additional parameter
-  \tcode{perm_options} \tcode{opts} with an argument of \tcode{perm_options::replace}.
+\remarks
+The second signature behaves as if it had an additional parameter
+\tcode{perm_options} \tcode{opts} with an argument of \tcode{perm_options::replace}.
 
 \pnum
-  \effects Applies the action specified by \tcode{opts}
-  to the file \tcode{p} resolves to,
-  or to file \tcode{p} itself if \tcode{p} is a symbolic link
-  and \tcode{perm_options::nofollow} is set in \tcode{opts}.
-  The action is applied as if by POSIX \tcode{fchmodat()}.
+\effects
+Applies the action specified by \tcode{opts}
+to the file \tcode{p} resolves to,
+or to file \tcode{p} itself if \tcode{p} is a symbolic link
+and \tcode{perm_options::nofollow} is set in \tcode{opts}.
+The action is applied as if by POSIX \tcode{fchmodat()}.
 
 \pnum
 \begin{note}
 Conceptually permissions are viewed as bits, but the actual
-  implementation may use some other mechanism.
+implementation may use some other mechanism.
 \end{note}
 
 \pnum