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P2071R2 Named universal character escapes
Wording for the paper P2071R2 Named universal character escapes, actually an alternate form of universal-character-name, as reviewed and approved by CWG. Not yet approved by plenary. Needs final date for feature test macro.
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‎source/lex.tex

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@@ -288,6 +288,25 @@
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The \grammarterm{universal-character-name} construct provides a way to name
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other characters.
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\begin{bnf}
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\nontermdef{n-char} \textnormal{one of}\br
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\terminal{A B C D E F G H I J K L M N O P Q R S T U V W X Y Z}\br
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\terminal{0 1 2 3 4 5 6 7 8 9}\br
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\textnormal{\unicode{002d}{hyphen-minus}}\br
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\textnormal{\unicode{0020}{space}}
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\end{bnf}
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\begin{bnf}
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\nontermdef{n-char-sequence}\br
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n-char\br
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n-char-sequence n-char
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\end{bnf}
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\begin{bnf}
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\nontermdef{named-universal-character}\br
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\terminal{\textbackslash N\{n-char-sequence\}}
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\end{bnf}
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\begin{bnf}
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\nontermdef{hex-quad}\br
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hexadecimal-digit hexadecimal-digit hexadecimal-digit hexadecimal-digit
@@ -296,15 +315,138 @@
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\begin{bnf}
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\nontermdef{universal-character-name}\br
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\terminal{\textbackslash u} hex-quad\br
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\terminal{\textbackslash U} hex-quad hex-quad
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\terminal{\textbackslash U} hex-quad hex-quad\br
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named-universal-character
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\end{bnf}
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\pnum
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A \grammarterm{universal-character-name}
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of the form \textbackslash u \grammarterm{hex-quad} or \textbackslash U
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\grammarterm{hex-quad} \grammarterm{hex-quad}
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designates the character in the translation character set
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whose UCS scalar value is the hexadecimal number represented by
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the sequence of \grammarterm{hexadecimal-digit}s
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in the \grammarterm{universal-character-name}.
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The program is ill-formed if that number is not a UCS scalar value.
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\pnum
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A \grammarterm{universal-character-name} that is a
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\grammarterm{named-universal-character} designates the
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character named by its \grammarterm{n-char-sequence}. A character is so named if the
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\grammarterm{n-char-sequence} is equal to
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\begin{itemize}
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\item the associated character name or associated character name alias specified in
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ISO/IEC 10646 subclause ``Code charts and lists of character names'' or
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\item the control code alias given in \tref{lex.charset.aliases}.
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\begin{note}
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The aliases in \tref{lex.charset.aliases} are provided for control characters
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which otherwise have no associated character name or character name alias.
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These names are derived from the Unicode Character Database's \tcode{NameAliases.txt}.
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For historical reasons, control characters are formally unnamed.
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\end{note}
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\end{itemize}
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\begin{note}
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None of the associated character names, associated character name aliases, or
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control code aliases have leading or trailing spaces.
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\end{note}
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\begin{LongTable}{Control Code Aliases}{lex.charset.aliases}{ll}
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\\ \topline
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\lhdr{Code point} & \rhdr{Control code alias} \\ \capsep
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\endfirsthead
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\continuedcaption \\
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\hline
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\lhdr{Code point} & \rhdr{Control code alias} \\ \capsep
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\endhead
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\ucode{0000} & \tcode{NULL} \\ \rowsep
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\ucode{0001} & \tcode{START OF HEADING} \\ \rowsep
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\ucode{0002} & \tcode{START OF TEXT} \\ \rowsep
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\ucode{0003} & \tcode{END OF TEXT} \\ \rowsep
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\ucode{0004} & \tcode{END OF TRANSMISSION} \\ \rowsep
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\ucode{0005} & \tcode{ENQUIRY} \\ \rowsep
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\ucode{0006} & \tcode{ACKNOWLEDGE} \\ \rowsep
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\ucode{0007} & \tcode{ALERT} \\ \rowsep
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\ucode{0008} & \tcode{BACKSPACE} \\ \rowsep
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\ucode{0009} & \tcode{CHARACTER TABULATION} \\
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& \tcode{HORIZONTAL TABULATION} \\ \rowsep
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\ucode{000a} & \tcode{LINE FEED} \\
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& \tcode{NEW LINE} \\
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& \tcode{END OF LINE} \\ \rowsep
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\ucode{000b} & \tcode{LINE TABULATION} \\
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& \tcode{VERTICAL TABULATION} \\ \rowsep
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\ucode{000c} & \tcode{FORM FEED} \\ \rowsep
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\ucode{000d} & \tcode{CARRIAGE RETURN} \\ \rowsep
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\ucode{000e} & \tcode{SHIFT OUT} \\
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& \tcode{LOCKING-SHIFT ONE} \\ \rowsep
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\ucode{000f} & \tcode{SHIFT IN} \\
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& \tcode{LOCKING-SHIFT ZERO} \\ \rowsep
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\ucode{0010} & \tcode{DATA LINK ESCAPE} \\ \rowsep
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\ucode{0011} & \tcode{DEVICE CONTROL ONE} \\ \rowsep
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\ucode{0012} & \tcode{DEVICE CONTROL TWO} \\ \rowsep
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\ucode{0013} & \tcode{DEVICE CONTROL THREE} \\ \rowsep
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\ucode{0014} & \tcode{DEVICE CONTROL FOUR} \\ \rowsep
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\ucode{0015} & \tcode{NEGATIVE ACKNOWLEDGE} \\ \rowsep
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\ucode{0016} & \tcode{SYNCHRONOUS IDLE} \\ \rowsep
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\ucode{0017} & \tcode{END OF TRANSMISSION BLOCK} \\ \rowsep
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\ucode{0018} & \tcode{CANCEL} \\ \rowsep
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\ucode{0019} & \tcode{END OF MEDIUM} \\ \rowsep
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\ucode{001a} & \tcode{SUBSTITUTE} \\ \rowsep
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\ucode{001b} & \tcode{ESCAPE} \\ \rowsep
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\ucode{001c} & \tcode{INFORMATION SEPARATOR FOUR} \\
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& \tcode{FILE SEPARATOR} \\ \rowsep
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\ucode{001d} & \tcode{INFORMATION SEPARATOR THREE} \\
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& \tcode{GROUP SEPARATOR} \\ \rowsep
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\ucode{001e} & \tcode{INFORMATION SEPARATOR TWO} \\
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& \tcode{RECORD SEPARATOR} \\ \rowsep
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\ucode{001f} & \tcode{INFORMATION SEPARATOR ON} \\
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& \tcode{UNIT SEPARATOR} \\ \rowsep
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\ucode{007f} & \tcode{DELETE} \\ \rowsep
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\ucode{0082} & \tcode{BREAK PERMITTED HERE} \\ \rowsep
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\ucode{0083} & \tcode{NO BREAK HERE} \\ \rowsep
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\ucode{0084} & \tcode{INDEX} \\ \rowsep
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\ucode{0085} & \tcode{NEXT LINE} \\ \rowsep
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\ucode{0086} & \tcode{START OF SELECTED AREA} \\ \rowsep
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\ucode{0087} & \tcode{END OF SELECTED AREA} \\ \rowsep
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\ucode{0088} & \tcode{CHARACTER TABULATION SET} \\
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& \tcode{HORIZONTAL TABULATION SET} \\ \rowsep
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\ucode{0089} & \tcode{CHARACTER TABULATION WITH JUSTIFICATION} \\
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& \tcode{HORIZONTAL TABULATION WITH JUSTIFICATION} \\ \rowsep
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\ucode{008a} & \tcode{LINE TABULATION SET} \\
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& \tcode{VERTICAL TABULATION SET} \\ \rowsep
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\ucode{008b} & \tcode{PARTIAL LINE FORWARD} \\
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& \tcode{PARTIAL LINE DOWN} \\ \rowsep
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\ucode{008c} & \tcode{PARTIAL LINE BACKWARD} \\
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& \tcode{PARTIAL LINE UP} \\ \rowsep
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\ucode{008d} & \tcode{REVERSE LINE FEED} \\
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& \tcode{REVERSE INDEX} \\ \rowsep
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\ucode{008e} & \tcode{SINGLE SHIFT TWO} \\
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& \tcode{SINGLE-SHIFT-2} \\ \rowsep
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\ucode{008f} & \tcode{SINGLE SHIFT THREE} \\
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& \tcode{SINGLE-SHIFT-3} \\ \rowsep
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\ucode{0090} & \tcode{DEVICE CONTROL STRING} \\ \rowsep
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\ucode{0091} & \tcode{PRIVATE USE ONE} \\
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& \tcode{PRIVATE USE-1} \\ \rowsep
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\ucode{0092} & \tcode{PRIVATE USE TWO} \\
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& \tcode{PRIVATE USE-2} \\ \rowsep
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\ucode{0093} & \tcode{SET TRANSMIT STATE} \\ \rowsep
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\ucode{0094} & \tcode{CANCEL CHARACTER} \\ \rowsep
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\ucode{0095} & \tcode{MESSAGE WAITING} \\ \rowsep
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\ucode{0096} & \tcode{START OF GUARDED AREA} \\
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& \tcode{START OF PROTECTED AREA} \\ \rowsep
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\ucode{0097} & \tcode{END OF GUARDED AREA} \\
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& \tcode{END OF PROTECTED AREA} \\ \rowsep
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\ucode{0098} & \tcode{START OF STRING} \\ \rowsep
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\ucode{009a} & \tcode{SINGLE CHARACTER INTRODUCER} \\ \rowsep
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\ucode{009b} & \tcode{CONTROL SEQUENCE INTRODUCER} \\ \rowsep
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\ucode{009c} & \tcode{STRING TERMINATOR} \\ \rowsep
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\ucode{009d} & \tcode{OPERATING SYSTEM COMMAND} \\ \rowsep
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\ucode{009e} & \tcode{PRIVACY MESSAGE} \\ \rowsep
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\ucode{009f} & \tcode{APPLICATION PROGRAM COMMAND} \\
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\end{LongTable}
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\pnum
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If a \grammarterm{universal-character-name} outside
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the \grammarterm{c-char-sequence}, \grammarterm{s-char-sequence}, or
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\grammarterm{r-char-sequence} of
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\begin{bnf}
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\nontermdef{conditional-escape-sequence-char}\br
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\textnormal{any member of the basic character set that is not an} octal-digit\textnormal{, a} simple-escape-sequence-char\textnormal{, or the characters \terminal{u}, \terminal{U}, or \terminal{x}}
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\textnormal{any member of the basic character set that is not an} octal-digit\textnormal{, a} simple-escape-sequence-char\textnormal{, or the characters \terminal{N}, \terminal{u}, \terminal{U}, or \terminal{x}}
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\end{bnf}
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\pnum

‎source/preprocessor.tex

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\defnxname{cpp_lambdas} & \tcode{200907L} \\ \rowsep
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\defnxname{cpp_modules} & \tcode{201907L} \\ \rowsep
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\defnxname{cpp_multidimensional_subscript} & \tcode{202110L} \\ \rowsep
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\defnxname{cpp_named_character_escapes} & \tcode{XXXXXXL} \\ \rowsep % FIXME IF PLENARY ADOPTS
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\defnxname{cpp_namespace_attributes} & \tcode{201411L} \\ \rowsep
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\defnxname{cpp_noexcept_function_type} & \tcode{201510L} \\ \rowsep
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\defnxname{cpp_nontype_template_args} & \tcode{201911L} \\ \rowsep

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