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  • doc/LaTeXmacros/common.tex

    r08061589 r182fe1e  
    1010%% Author           : Peter A. Buhr
    1111%% Created On       : Sat Apr  9 10:06:17 2016
     12<<<<<<< HEAD
     13%% Last Modified By : Peter A. Buhr
     14%% Last Modified On : Mon Aug  1 08:57:17 2016
     15%% Update Count     : 223
     16=======
    1217%% Last Modified By :
    1318%% Last Modified On : Sun Jul 31 07:22:50 2016
    1419%% Update Count     : 207
     20>>>>>>> 080615890f586cb9954c252b55cab47f52c25758
    1521%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    1622
    … …  
    1925\setlength{\textheight}{9in}
    2026%\oddsidemargin 0.0in
    21 \renewcommand{\topfraction}{0.8}        % float must be greater than X of the page before it is forced onto its own page
    22 \renewcommand{\bottomfraction}{0.8}     % float must be greater than X of the page before it is forced onto its own page
     27\renewcommand{\topfraction}{0.8}                % float must be greater than X of the page before it is forced onto its own page
     28\renewcommand{\bottomfraction}{0.8}             % float must be greater than X of the page before it is forced onto its own page
    2329\renewcommand{\floatpagefraction}{0.8}  % float must be greater than X of the page before it is forced onto its own page
    24 \renewcommand{\textfraction}{0.0}       % the entire page maybe devoted to floats with no text on the page at all
    25 
    26 \lefthyphenmin=4
     30\renewcommand{\textfraction}{0.0}               % the entire page maybe devoted to floats with no text on the page at all
     31
     32\lefthyphenmin=4                                                % hyphen only after 4 characters
    2733\righthyphenmin=4
    2834
    … …  
    3844% Names used in the document.
    3945
    40 \newcommand{\CFA}{C$\mathbf\forall$\xspace}              % set language symbolic name
    41 \newcommand{\CFL}{Cforall\xspace}                        % set language text name
     46\newcommand{\CFA}{C$\mathbf\forall$\xspace} % set language symbolic name
     47\newcommand{\CFL}{Cforall\xspace}               % set language text name
    4248\newcommand{\CC}{\rm C\kern-.1em\hbox{+\kern-.25em+}\xspace} % CC symbolic name
    4349\newcommand{\CCeleven}{\rm C\kern-.1em\hbox{+\kern-.25em+}11\xspace} % C++11 symbolic name
    44 \def\c11{ISO/IEC C} % C11 name (cannot have numbers in latex command name)
     50\def\c11{ISO/IEC C}                                             % C11 name (cannot have numbers in latex command name)
    4551
    4652%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    … …  
    5258\setlength{\parindentlnth}{\parindent}
    5359
    54 \newlength{\gcolumnposn}
     60\newlength{\gcolumnposn}                                % temporary hack because lstlisting does handle tabs correctly
    5561\newlength{\columnposn}
    5662\setlength{\gcolumnposn}{2.5in}
    … …  
    6369%\patchcmd{\lsthk@TextStyle}{\let\lst@DefEsc\@empty}{}{}{\errmessage{failed to patch}}
    6470
    65 \usepackage{pslatex}                                                                    % reduce size of san serif font
    66 \usepackage{relsize}                                    % must be after change to small or selects old size
     71\usepackage{pslatex}                                    % reduce size of san serif font
     72\usepackage{relsize}                                    % must be after change to small or selects old size
    6773
    6874% reduce size of chapter/section titles
    … …  
    120126
    121127% inline text and lowercase index: \Index{inline and lowercase index text}
     128\newcommand{\Index}{\@ifstar\@sIndex\@Index}
    122129% inline text and as-in index: \Index[as-is index text]{inline text}
     130\newcommand{\@Index}[2][\@empty]{\lowercase{\def\temp{#2}}#2\ifx#1\@empty\index{\temp}\else\index{#1@{\protect#2}}\fi}
    123131% inline text but index with different as-is text: \Index[index text]{inline text}
    124 \newcommand{\Index}{\@ifstar\@sIndex\@Index}
    125 \newcommand{\@Index}[2][\@empty]{\lowercase{\def\temp{#2}}#2\ifx#1\@empty\index{\temp}\else\index{#1@{\protect#2}}\fi}
    126132\newcommand{\@sIndex}[2][\@empty]{#2\ifx#1\@empty\index{#2}\else\index{#1@{\protect#2}}\fi}
    127133
    128 % cannot use ©
     134% inline text and code index (cannot use ©)
    129135\newcommand{\Indexc}[1]{\lstinline$#1$\index{#1@\lstinline$#1$}}
     136% code index (cannot use ©)
    130137\newcommand{\indexc}[1]{\index{#1@\lstinline$#1$}}
    131138
    … …  
    137144\newcommand{\@newterm}[2][\@empty]{\lowercase{\def\temp{#2}}{\newtermFontInline{#2}}\ifx#1\@empty\index{\temp}\else\index{#1@{\protect#2}}\fi}
    138145\newcommand{\@snewterm}[2][\@empty]{{\newtermFontInline{#2}}\ifx#1\@empty\index{#2}\else\index{#1@{\protect#2}}\fi}
     146
     147% Latin abbreviation
     148\newcommand{\abbrevFont}{\textit}       % set empty for no italics
     149\newcommand*{\eg}{%
     150        \@ifnextchar{,}{\abbrevFont{e}.\abbrevFont{g}.}%
     151                {\@ifnextchar{:}{\abbrevFont{e}.\abbrevFont{g}.}%
     152                        {\abbrevFont{e}.\abbrevFont{g}.,\xspace}}%
     153}%
     154\newcommand*{\ie}{%
     155        \@ifnextchar{,}{\abbrevFont{i}.\abbrevFont{e}.}%
     156                {\@ifnextchar{:}{\abbrevFont{i}.\abbrevFont{e}.}%
     157                        {\abbrevFont{i}.\abbrevFont{e}.,\xspace}}%
     158}%
     159\newcommand*{\etc}{%
     160        \@ifnextchar{.}{\abbrevFont{etc}}%
     161        {\abbrevFont{etc}.\xspace}%
     162}%
    139163\makeatother
    140164
    … …  
    145169        \endlist
    146170}% quote2
     171
    147172\newenvironment{rationale}{%
    148173  \begin{quote2}\noindent$\Box$\enspace
    … …  
    188213\newcommand{\VPageref}[2][page]{\ifx#1\@empty\else{#1}\nobreakspace\fi\pageref{#2}}
    189214
    190 % Go programming language
     215% Go programming language: https://github.com/julienc91/listings-golang/blob/master/listings-golang.sty
    191216\lstdefinelanguage{Golang}{
    192217        morekeywords=[1]{package,import,func,type,struct,return,defer,panic, recover,select,var,const,iota,},%
    … …  
    204229}
    205230
    206 % CFA programming language, based on ANSI C
     231% CFA programming language, based on ANSI C (with some gcc additions)
    207232\lstdefinelanguage{CFA}[ANSI]{C}{
    208233        morekeywords={_Alignas,_Alignof,__alignof,__alignof__,asm,__asm,__asm__,_At,_Atomic,__attribute,__attribute__,auto,
    … …  
    215240language=CFA,
    216241columns=fullflexible,
    217 basicstyle=\linespread{0.9}\sf,
    218 stringstyle=\tt,
    219 tabsize=4,
    220 xleftmargin=\parindentlnth,
    221 extendedchars=true,
    222 escapechar=§,
    223 mathescape=true,
    224 keepspaces=true,
    225 showstringspaces=false,
    226 showlines=true,
    227 aboveskip=4pt,
     242basicstyle=\linespread{0.9}\sf,                 % reduce line spacing and use sanserif font
     243stringstyle=\tt,                                                % use typewriter font
     244tabsize=4,                                                              % 4 space tabbing
     245xleftmargin=\parindentlnth,                             % indent code to paragraph indentation
     246extendedchars=true,                                             % allow ASCII characters in the range 128-255
     247escapechar=§,                                                   % escape to latex in CFA code
     248mathescape=true,                                                % allow $...$ LaTeX math escapes in code
     249%keepspaces=true,                                               %
     250showstringspaces=false,                                 % do not show spaces with cup
     251showlines=true,                                                 % show blank lines at end of code
     252aboveskip=4pt,                                                  % spacing above/below code block
    228253belowskip=3pt,
    229 moredelim=**[is][\color{red}]{®}{®}, % red highlighting
    230 moredelim=**[is][\color{blue}]{ß}{ß}, % blue highlighting
     254moredelim=**[is][\color{red}]{®}{®},    % red highlighting
     255moredelim=**[is][\color{blue}]{ß}{ß},   % blue highlighting
    231256moredelim=**[is][\color{OliveGreen}]{¢}{¢}, % green highlighting
    232257moredelim=[is][\lstset{keywords={}}]{¶}{¶}, % temporarily turn off keywords
    … …  
    242267\renewcommand\thebibliography[1]{
    243268  \Oldthebibliography{#1}
    244   \setlength{\parskip}{0pt}                     % reduce vertical spacing between references
     269  \setlength{\parskip}{0pt}                             % reduce vertical spacing between references
    245270  \setlength{\itemsep}{5pt plus 0.3ex}
    246271}%
    247 
    248 \newcommand*{\eg}{\textit{e.g}.\@\xspace}
    249 \newcommand*{\ie}{\textit{i.e}.\@\xspace}
    250 
    251 \makeatletter
    252 \newcommand*{\etc}{%
    253     \@ifnextchar{.}%
    254         {\textit{etc}}%
    255         {\textit{etc}.\@\xspace}%
    256 }
    257 \makeatother
    258272
    259273% Local Variables: %

  • doc/user/user.tex

    r08061589 r182fe1e  
    1010%% Author           : Peter A. Buhr
    1111%% Created On       : Wed Apr  6 14:53:29 2016
     12<<<<<<< HEAD
     13%% Last Modified By : Peter A. Buhr
     14%% Last Modified On : Mon Aug  1 08:43:49 2016
     15%% Update Count     : 1270
     16=======
    1217%% Last Modified By :
    1318%% Last Modified On : Sun Jul 31 07:27:55 2016
    1419%% Update Count     : 1254
     20>>>>>>> 080615890f586cb9954c252b55cab47f52c25758
    1521%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    1622
    … …  
    211217however, it largely extended the language, and did not address many existing problems.\footnote{%
    212218Two important existing problems addressed were changing the type of character literals from ©int© to ©char© and enumerator from ©int© to the type of its enumerators.}
    213 \Index*{Fortran}~\cite{Fortran08}, \Index*{Ada}~\cite{Ada12}, and \Index*{Cobol}~\cite{Cobol14} are examples of programming languages that took an evolutionary approach, where modern language features (e.g., objects, concurrency) are added and problems fixed within the framework of the existing language.
     219\Index*{Fortran}~\cite{Fortran08}, \Index*{Ada}~\cite{Ada12}, and \Index*{Cobol}~\cite{Cobol14} are examples of programming languages that took an evolutionary approach, where modern language features (\eg objects, concurrency) are added and problems fixed within the framework of the existing language.
    214220\Index*{Java}~\cite{Java8}, \Index*{Go}~\cite{Go}, \Index*{Rust}~\cite{Rust} and \Index*{D}~\cite{D} are examples of the revolutionary approach for modernizing C/\CC, resulting in a new language rather than an extension of the descendent.
    215221These languages have different syntax and semantics from C, and do not interoperate directly with C, largely because of garbage collection.
    … …  
    265271\section[Compiling CFA Program]{Compiling \CFA Program}
    266272
    267 The command ©cfa© is used to compile \CFA program(s), and is based on the GNU \Indexc{gcc} command, e.g.:
     273The command ©cfa© is used to compile \CFA program(s), and is based on the GNU \Indexc{gcc} command, \eg:
    268274\begin{lstlisting}
    269275cfa§\indexc{cfa}\index{compilation!cfa@©cfa©}§ [ gcc-options ] C/§\CFA§-files [ assembler/loader-files ]
    … …  
    350356\section{Underscores in Constants}
    351357
    352 Numeric constants are extended to allow \Index{underscore}s within constants\index{constant!underscore}, e.g.:
     358Numeric constants are extended to allow \Index{underscore}s within constants\index{constant!underscore}, \eg:
    353359\begin{lstlisting}
    3543602®_®147®_®483®_®648;                    §\C{// decimal constant}§
    … …  
    366372\begin{enumerate}
    367373\item
    368 A sequence of underscores is disallowed, e.g., ©12__34© is invalid.
     374A sequence of underscores is disallowed, \eg ©12__34© is invalid.
    369375\item
    370376Underscores may only appear within a sequence of digits (regardless of the digit radix).
    371 In other words, an underscore cannot start or end a sequence of digits, e.g., ©_1©, ©1_© and ©_1_© are invalid (actually, the 1st and 3rd examples are identifier names).
     377In other words, an underscore cannot start or end a sequence of digits, \eg ©_1©, ©1_© and ©_1_© are invalid (actually, the 1st and 3rd examples are identifier names).
    372378\item
    373379A numeric prefix may end with an underscore;
    … …  
    498504\end{quote2}
    499505
    500 All type qualifiers, e.g., ©const©, ©volatile©, etc., are used in the normal way with the new declarations and also appear left to right, e.g.:
     506All type qualifiers, \eg ©const©, ©volatile©, etc., are used in the normal way with the new declarations and also appear left to right, \eg:
    501507\begin{quote2}
    502508\begin{tabular}{@{}l@{\hspace{1em}}l@{\hspace{1em}}l@{}}
    … …  
    518524\end{tabular}
    519525\end{quote2}
    520 All declaration qualifiers, e.g., ©extern©, ©static©, etc., are used in the normal way with the new declarations but can only appear at the start of a \CFA routine declaration,\footnote{\label{StorageClassSpecifier}
    521 The placement of a storage-class specifier other than at the beginning of the declaration specifiers in a declaration is an obsolescent feature.~\cite[\S~6.11.5(1)]{C11}} e.g.:
     526All declaration qualifiers, \eg ©extern©, ©static©, etc., are used in the normal way with the new declarations but can only appear at the start of a \CFA routine declaration,\footnote{\label{StorageClassSpecifier}
     527The placement of a storage-class specifier other than at the beginning of the declaration specifiers in a declaration is an obsolescent feature.~\cite[\S~6.11.5(1)]{C11}} \eg:
    522528\begin{quote2}
    523529\begin{tabular}{@{}l@{\hspace{3em}}l@{\hspace{2em}}l@{}}
    … …  
    542548Unsupported are K\&R C declarations where the base type defaults to ©int©, if no type is specified,\footnote{
    543549At least one type specifier shall be given in the declaration specifiers in each declaration, and in the specifier-qualifier list in each structure declaration and type name~\cite[\S~6.7.2(2)]{C11}}
    544 e.g.:
     550\eg:
    545551\begin{lstlisting}
    546552x;                                                              §\C{// int x}§
    … …  
    612618A \Index{pointer}/\Index{reference} is a generalization of a variable name, i.e., a mutable address that can point to more than one memory location during its lifetime.
    613619(Similarly, an integer variable can contain multiple integer literals during its lifetime versus an integer constant representing a single literal during its lifetime and may not occupy storage as the literal is embedded directly into instructions.)
    614 Hence, a pointer occupies memory to store its current address, and the pointer's value is loaded by dereferencing, e.g.:
     620Hence, a pointer occupies memory to store its current address, and the pointer's value is loaded by dereferencing, \eg:
    615621\begin{quote2}
    616622\begin{tabular}{@{}ll@{}}
    … …  
    669675Except for auto-dereferencing by the compiler, this reference example is the same as the previous pointer example.
    670676Hence, a reference behaves like the variable name for the current variable it is pointing-to.
    671 The simplest way to understand a reference is to imagine the compiler inserting a dereference operator before the reference variable for each reference qualifier in a declaration, e.g.:
     677The simplest way to understand a reference is to imagine the compiler inserting a dereference operator before the reference variable for each reference qualifier in a declaration, \eg:
    672678\begin{lstlisting}
    673679r2 = ((r1 + r2) * (r3 - r1)) / (r3 - 15);
    … …  
    677683®*®r2 = ((®*®r1 + ®*®r2) ®*® (®**®r3 - ®*®r1)) / (®**®r3 - 15);
    678684\end{lstlisting}
    679 When a reference operation appears beside a dereference operation, e.g., ©&*©, they cancel out.\footnote{
     685When a reference operation appears beside a dereference operation, \eg ©&*©, they cancel out.\footnote{
    680686The unary ©&© operator yields the address of its operand.
    681687If the operand has type ``type'', the result has type ``pointer to type''.
    … …  
    721727®&®crc = &cx;                                   §\C{// error, cannot change crc}§
    722728\end{lstlisting}
    723 Hence, for type ©& const©, there is no pointer assignment, so ©&rc = &x© is disallowed, and \emph{the address value cannot be ©0© unless an arbitrary pointer is assigned to the reference}, e.g.:
     729Hence, for type ©& const©, there is no pointer assignment, so ©&rc = &x© is disallowed, and \emph{the address value cannot be ©0© unless an arbitrary pointer is assigned to the reference}, \eg:
    724730\begin{lstlisting}
    725731int & const r = *0;                             §\C{// where 0 is the int * zero}§
    726732\end{lstlisting}
    727733Otherwise, the compiler is managing the addresses for type ©& const© not the programmer, and by a programming discipline of only using references with references, address errors can be prevented.
     734Finally, the position of the ©const© qualifier \emph{after} the pointer/reference qualifier causes confuse for C programmers.
     735The ©const© qualifier cannot be moved before the pointer/reference qualifier for C style-declarations;
     736\CFA-style declarations attempt to address this issue:
     737\begin{quote2}
     738\begin{tabular}{@{}l@{\hspace{3em}}l@{}}
     739\multicolumn{1}{c@{\hspace{3em}}}{\textbf{\CFA}}        & \multicolumn{1}{c}{\textbf{C}}        \\
     740\begin{lstlisting}
     741®const® * ®const® * const int ccp;
     742®const® & ®const® & const int ccr;
     743\end{lstlisting}
     744&
     745\begin{lstlisting}
     746const int * ®const® * ®const® ccp;
     747
     748\end{lstlisting}
     749\end{tabular}
     750\end{quote2}
     751where the \CFA declaration is read left-to-right (see \VRef{s:Declarations}).
    728752
    729753\Index{Initialization} is different than \Index{assignment} because initialization occurs on the empty (uninitialized) storage on an object, while assignment occurs on possibly initialized storage of an object.
    … …  
    785809\section{Type Operators}
    786810
    787 The new declaration syntax can be used in other contexts where types are required, e.g., casts and the pseudo-routine ©sizeof©:
     811The new declaration syntax can be used in other contexts where types are required, \eg casts and the pseudo-routine ©sizeof©:
    788812\begin{quote2}
    789813\begin{tabular}{@{}l@{\hspace{3em}}l@{}}
    … …  
    805829
    806830\CFA also supports a new syntax for routine definition, as well as ISO C and K\&R routine syntax.
    807 The point of the new syntax is to allow returning multiple values from a routine~\cite{Galletly96,CLU}, e.g.:
     831The point of the new syntax is to allow returning multiple values from a routine~\cite{Galletly96,CLU}, \eg:
    808832\begin{lstlisting}
    809833®[ int o1, int o2, char o3 ]® f( int i1, char i2, char i3 ) {
    … …  
    817841\Index*{Michael Tiemann}, with help from \Index*{Doug Lea}, provided named return values in g++, circa 1989.}
    818842The value of each local return variable is automatically returned at routine termination.
    819 Declaration qualifiers can only appear at the start of a routine definition, e.g.:
     843Declaration qualifiers can only appear at the start of a routine definition, \eg:
    820844\begin{lstlisting}
    821845®extern® [ int x ] g( int y ) {§\,§}
    … …  
    849873The inability to use \CFA declarations in these two contexts is probably a blessing because it precludes programmers from arbitrarily switching between declarations forms within a declaration contexts.
    850874
    851 C-style declarations can be used to declare parameters for \CFA style routine definitions, e.g.:
     875C-style declarations can be used to declare parameters for \CFA style routine definitions, \eg:
    852876\begin{lstlisting}
    853877[ int ] f( * int, int * );              §\C{// returns an integer, accepts 2 pointers to integers}§
    … …  
    898922
    899923The syntax of the new routine prototype declaration follows directly from the new routine definition syntax;
    900 as well, parameter names are optional, e.g.:
     924as well, parameter names are optional, \eg:
    901925\begin{lstlisting}
    902926[ int x ] f ();                                 §\C{// returning int with no parameters}§
    … …  
    906930\end{lstlisting}
    907931This syntax allows a prototype declaration to be created by cutting and pasting source text from the routine definition header (or vice versa).
    908 It is possible to declare multiple routine-prototypes in a single declaration, but the entire type specification is distributed across \emph{all} routine names in the declaration list (see~\VRef{s:Declarations}), e.g.:
     932It is possible to declare multiple routine-prototypes in a single declaration, but the entire type specification is distributed across \emph{all} routine names in the declaration list (see~\VRef{s:Declarations}), \eg:
    909933\begin{quote2}
    910934\begin{tabular}{@{}l@{\hspace{3em}}l@{}}
    … …  
    919943\end{tabular}
    920944\end{quote2}
    921 Declaration qualifiers can only appear at the start of a \CFA routine declaration,\footref{StorageClassSpecifier} e.g.:
     945Declaration qualifiers can only appear at the start of a \CFA routine declaration,\footref{StorageClassSpecifier} \eg:
    922946\begin{lstlisting}
    923947extern [ int ] f (int);
    … …  
    928952\section{Routine Pointers}
    929953
    930 The syntax for pointers to \CFA routines specifies the pointer name on the right, e.g.:
     954The syntax for pointers to \CFA routines specifies the pointer name on the right, \eg:
    931955\begin{lstlisting}
    932956* [ int x ] () fp;                      §\C{// pointer to routine returning int with no parameters}§
    … …  
    10461070p( /* positional */, /* named */, . . . );
    10471071\end{lstlisting}
    1048 While it is possible to implement both approaches, the first possibly is more complex than the second, e.g.:
     1072While it is possible to implement both approaches, the first possibly is more complex than the second, \eg:
    10491073\begin{lstlisting}
    10501074p( int x, int y, int z, . . . );
    … …  
    10561080In the second call, the named arguments separate the positional and ellipse arguments, making it trivial to read the call.
    10571081
    1058 The problem is exacerbated with default arguments, e.g.:
     1082The problem is exacerbated with default arguments, \eg:
    10591083\begin{lstlisting}
    10601084void p( int x, int y = 2, int z = 3. . . );
    … …  
    12641288
    12651289As mentioned, tuples can appear in contexts requiring a list of value, such as an argument list of a routine call.
    1266 In unambiguous situations, the tuple brackets may be omitted, e.g., a tuple that appears as an argument may have its
     1290In unambiguous situations, the tuple brackets may be omitted, \eg a tuple that appears as an argument may have its
    12671291square brackets omitted for convenience; therefore, the following routine invocations are equivalent:
    12681292\begin{lstlisting}
    … …  
    13031327
    13041328Type qualifiers, i.e., const and volatile, may modify a tuple type.
    1305 The meaning is the same as for a type qualifier modifying an aggregate type [Int99, x 6.5.2.3(7),x 6.7.3(11)], i.e., the qualifier is distributed across all of the types in the tuple, e.g.:
     1329The meaning is the same as for a type qualifier modifying an aggregate type [Int99, x 6.5.2.3(7),x 6.7.3(11)], i.e., the qualifier is distributed across all of the types in the tuple, \eg:
    13061330\begin{lstlisting}
    13071331const volatile [ int, float, const int ] x;
    … …  
    13111335[ const volatile int, const volatile float, const volatile int ] x;
    13121336\end{lstlisting}
    1313 Declaration qualifiers can only appear at the start of a \CFA tuple declaration4, e.g.:
     1337Declaration qualifiers can only appear at the start of a \CFA tuple declaration4, \eg:
    13141338\begin{lstlisting}
    13151339extern [ int, int ] w1;
    … …  
    13191343Unfortunately, C's syntax for subscripts precluded treating them as tuples.
    13201344The C subscript list has the form ©[i][j]...© and not ©[i, j, ...]©.
    1321 Therefore, there is no syntactic way for a routine returning multiple values to specify the different subscript values, e.g., ©f[g()]© always means a single subscript value because there is only one set of brackets.
     1345Therefore, there is no syntactic way for a routine returning multiple values to specify the different subscript values, \eg ©f[g()]© always means a single subscript value because there is only one set of brackets.
    13221346Fixing this requires a major change to C because the syntactic form ©M[i, j, k]© already has a particular meaning: ©i, j, k© is a comma expression.
    13231347\end{rationale}
    … …  
    13801404Clearly, the types of the entities being assigned must be type compatible with the value of the expression.
    13811405
    1382 Mass assignment has parallel semantics, e.g., the statement:
     1406Mass assignment has parallel semantics, \eg the statement:
    13831407\begin{lstlisting}
    13841408[ x, y, z ] = 1.5;
    … …  
    14691493\section{Unnamed Structure Fields}
    14701494
    1471 C requires each field of a structure to have a name, except for a bit field associated with a basic type, e.g.:
     1495C requires each field of a structure to have a name, except for a bit field associated with a basic type, \eg:
    14721496\begin{lstlisting}
    14731497struct {
    1474         int f1;                 // named field
    1475         int f2 : 4;             // named field with bit field size
    1476         int : 3;                // unnamed field for basic type with bit field size
    1477         int ;                   // disallowed, unnamed field
    1478         int *;                  // disallowed, unnamed field
    1479         int (*)(int);   // disallowed, unnamed field
     1498        int f1;                                 §\C{// named field}§
     1499        int f2 : 4;                             §\C{// named field with bit field size}§
     1500        int : 3;                                §\C{// unnamed field for basic type with bit field size}§
     1501        int ;                                   §\C{// disallowed, unnamed field}§
     1502        int *;                                  §\C{// disallowed, unnamed field}§
     1503        int (*)(int);                   §\C{// disallowed, unnamed field}§
    14801504};
    14811505\end{lstlisting}
    14821506This requirement is relaxed by making the field name optional for all field declarations; therefore, all the field declarations in the example are allowed.
    14831507As for unnamed bit fields, an unnamed field is used for padding a structure to a particular size.
    1484 A list of unnamed fields is also supported, e.g.:
     1508A list of unnamed fields is also supported, \eg:
    14851509\begin{lstlisting}
    14861510struct {
    1487         int , , ;               // 3 unnamed fields
     1511        int , , ;                               §\C{// 3 unnamed fields}§
    14881512}
    14891513\end{lstlisting}
    … …  
    14981522§\emph{expr}§ -> [ §\emph{fieldlist}§ ]
    14991523\end{lstlisting}
    1500 \emph{expr} is any expression yielding a value of type record, e.g., ©struct©, ©union©.
     1524\emph{expr} is any expression yielding a value of type record, \eg ©struct©, ©union©.
    15011525Each element of \emph{ fieldlist} is an element of the record specified by \emph{expr}.
    15021526A record-field tuple may be used anywhere a tuple can be used. An example of the use of a record-field tuple is
    … …  
    17601784}
    17611785\end{lstlisting}
    1762 While the declaration of the local variable ©y© is useful and its scope is across all ©case© clauses, the initialization for such a variable is defined to never be executed because control always transfers over it.
    1763 Furthermore, any statements before the first ©case© clause can only be executed if labelled and transferred to using a ©goto©, either from outside or inside of the ©switch©.
    1764 As mentioned, transfer into control structures should be forbidden;
    1765 transfers from within the ©switch© body using a ©goto© are equally unpalatable.
    1766 As well, the declaration of ©z© is cannot occur after the ©case© because a label can only be attached to a statement, and without a fall through to case 3, ©z© is uninitialized.
     1786While the declaration of the local variable ©y© is useful with a scope across all ©case© clauses, the initialization for such a variable is defined to never be executed because control always transfers over it.
     1787Furthermore, any statements before the first ©case© clause can only be executed if labelled and transferred to using a ©goto©, either from outside or inside of the ©switch©, both of which are problematic.
     1788As well, the declaration of ©z© cannot occur after the ©case© because a label can only be attached to a statement, and without a fall through to case 3, ©z© is uninitialized.
     1789The key observation is that the ©switch© statement branches into control structure, i.e., there are multiple entry points into its statement body.
    17671790\end{enumerate}
    17681791
    … …  
    17821805\item
    17831806Eliminating default fall-through has the greatest potential for affecting existing code.
    1784 However, even if fall-through is removed, most ©switch© statements would continue to work because of the explicit transfers already present at the end of each ©case© clause, the common placement of the ©default© clause at the end of the case list, and the most common use of fall-through, i.e., a list of ©case© clauses executing common code, e.g.:
    1785 \begin{lstlisting}
     1807However, even if fall-through is removed, most ©switch© statements would continue to work because of the explicit transfers already present at the end of each ©case© clause, the common placement of the ©default© clause at the end of the case list, and the most common use of fall-through, i.e., a list of ©case© clauses executing common code, \eg:
     1808 \begin{lstlisting}
    17861809case 1:  case 2:  case 3: ...
    17871810\end{lstlisting}
    17881811still work.
    17891812Nevertheless, reversing the default action would have a non-trivial effect on case actions that compound, such as the above example of processing shell arguments.
     1813<<<<<<< HEAD
     1814Therefore, to preserve backwards compatibility, it is necessary to introduce a new kind of ©switch© statement, called ©choose©, with no implicit fall-through semantics and an explicit fall-through if the last statement of a case-clause ends with the new keyword ©fallthru©, \eg:
     1815=======
    17901816Therefore, to preserve backwards compatibility, it is necessary to introduce a new kind of ©switch© statement, called ©choose©, with no implicit fall-through semantics and an explicit fall-through if the last statement of a case-clause ends with the new keyword ©fallthrough©/©fallthru©, e.g.:
     1817>>>>>>> 080615890f586cb9954c252b55cab47f52c25758
    17911818\begin{lstlisting}
    17921819®choose® ( i ) {
    … …  
    18151842Therefore, no change is made for this issue.
    18161843\item
    1817 Dealing with unreachable code in a ©switch©/©choose© body is solved by restricting declarations and associated initialization to the start of statement body, which is executed \emph{before} the transfer to the appropriate ©case© clause.\footnote{
    1818 Essentially, these declarations are hoisted before the statement and both declarations and statement are surrounded by a compound statement.} and precluding statements before the first ©case© clause.
    1819 Further declaration in the statement body are disallowed.
     1844Dealing with unreachable code in a ©switch©/©choose© body is solved by restricting declarations and associated initialization to the start of statement body, which is executed \emph{before} the transfer to the appropriate ©case© clause\footnote{
     1845Essentially, these declarations are hoisted before the ©switch©/©choose© statement and both declarations and statement are surrounded by a compound statement.} and precluding statements before the first ©case© clause.
     1846Further declarations at the same nesting level as the statement body are disallowed to ensure every transfer into the body is sound.
    18201847\begin{lstlisting}
    18211848switch ( x ) {
    1822         ®int i = 0;®                            §\C{// allowed}§
     1849        ®int i = 0;®                            §\C{// allowed only at start}§
    18231850  case 0:
    18241851        ...
    1825         ®int i = 0;®                            §\C{// disallowed}§
     1852        ®int j = 0;®                            §\C{// disallowed}§
    18261853  case 1:
    18271854    {
    1828                 ®int i = 0;®                    §\C{// allowed in any compound statement}§
     1855                ®int k = 0;®                    §\C{// allowed at different nesting levels}§
    18291856                ...
    18301857        }
    … …  
    27072734Like the \Index*[C++]{\CC} lexical problem with closing template-syntax, e.g, ©Foo<Bar<int®>>®©, this issue can be solved with a more powerful lexer/parser.
    27082735
    2709 There are several ambiguous cases with operator identifiers, e.g., ©int *?*?()©, where the string ©*?*?© can be lexed as ©*©/©?*?© or ©*?©/©*?©.
    2710 Since it is common practise to put a unary operator juxtaposed to an identifier, e.g., ©*i©, users will be annoyed if they cannot do this with respect to operator identifiers.
     2736There are several ambiguous cases with operator identifiers, \eg ©int *?*?()©, where the string ©*?*?© can be lexed as ©*©/©?*?© or ©*?©/©*?©.
     2737Since it is common practise to put a unary operator juxtaposed to an identifier, \eg ©*i©, users will be annoyed if they cannot do this with respect to operator identifiers.
    27112738Even with this special hack, there are 5 general cases that cannot be handled.
    27122739The first case is for the function-call identifier ©?()©:
    … …  
    27732800This means that a function requiring mutual exclusion could block if the lock is already held by another thread.
    27742801Blocking on a monitor lock does not block the kernel thread, it simply blocks the user thread, which yields its kernel thread while waiting to obtain the lock.
    2775 If multiple mutex parameters are specified, they will be locked in parameter order (i.e. first parameter is locked first) and unlocked in the
     2802If multiple mutex parameters are specified, they will be locked in parameter order (\ie first parameter is locked first) and unlocked in the
    27762803reverse order.
    27772804\begin{lstlisting}
    … …  
    44764503\CFA is C \emph{incompatible} on this issue, and provides semantics similar to \Index*[C++]{\CC}.
    44774504Nested types are not hoisted and can be referenced using the field selection operator ``©.©'', unlike the \CC scope-resolution operator ``©::©''.
    4478 Given that nested types in C are equivalent to not using them, i.e., they are essentially useless, it is unlikely there are any realistic usages that break because of this incompatibility.
     4505Given that nested types in C are equivalent to not using them, \ie they are essentially useless, it is unlikely there are any realistic usages that break because of this incompatibility.
    44794506\end{description}
    44804507
    … …  
    51675194\label{s:RationalNumbers}
    51685195
    5169 Rational numbers are numbers written as a ratio, i.e., as a fraction, where the numerator (top number) and the denominator (bottom number) are whole numbers.
     5196Rational numbers are numbers written as a ratio, \ie as a fraction, where the numerator (top number) and the denominator (bottom number) are whole numbers.
    51705197When creating and computing with rational numbers, results are constantly reduced to keep the numerator and denominator as small as possible.
    51715198
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