\(
% cbs-katex.sty
%
\newcommand{\STYLE}[2]{\htmlClass{cbs-#1}{#2}}
\newcommand{\DECL}[3]{\htmlId{#1:#2}{#3}}
\newcommand{\REF}[3]{\href{###1:#2}{#3}}
\newcommand{\HYPER}[5]{\href{#1/#2/index.html###3:#4}{#5}}
% \SHADE{MATH} can be defined to produce a shaded background to highlight
% inline MATH in running text:
\newcommand{\SHADE}[1]{#1}
% \KEY{TEXT}, \STRING{TEXT}, \ATOM{TEXT}, \LEX{TEXT} can be used in math mode:
\newcommand{\KEY}[1]{\textsf{\textit{\STYLE{Key}{#1}}}}
\newcommand{\STRING}[1]{\textsf{``\texttt{#1}''}}
\newcommand{\ATOM}[1]{\textsf{`\texttt{#1}'}}
\newcommand{\LEX}[1]{\textsf{\STYLE{Key}{`}\texttt{#1}\STYLE{Key}{'}}}
% The following commands produce ASCII characters that are treated specially by LaTeX:
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\newcommand{\DOLLAR}{\char`\$}
\newcommand{\PERCENT}{\char`\%}
\newcommand{\AMPERSAND}{\char`\&}
\newcommand{\APOSTROPHE}{\char`\'}
\newcommand{\BACKSLASH}{\char`\\}
\newcommand{\CARET}{\char`\^}
\newcommand{\UNDERSCORE}{\char`\_}
\newcommand{\GRAVE}{\char`\`}
\newcommand{\LEFTBRACE}{\char`\{}
\newcommand{\RIGHTBRACE}{\char`\}}
\newcommand{\TILDE}{\textasciitilde} % {\char`\~}
% \NAME{name} highlights the name;
% \NAMEDECL{name} declares Name.name as the target of links to name;
% \NAMEREF{name} links name to the target Name.name in the current file;
% \NAMEHYPER{url}{file}{name} links name to Name.name at url/file/file.pdf.
% Similarly for \VAR{partvariable}, \SYN{syntaxname}, \SEM{semanticsName},
% and \SECT{sectionnumber}
% The kerns in \SUB and \VAR avoid overlaps with primes:
\newcommand{\SUB}[1]{_{\kern-2mu\STYLE{PartVariable}{\textsf{#1}}}}
% PLAIN
\newcommand{\VAR}[1]{\STYLE{PartVariable}{\textsf{\textit{#1}\kern2mu}}}
\newcommand{\NAME}[1]{\STYLE{Name}{\textsf{#1}}}
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\newcommand{\SEM}[1]{\STYLE{SemanticsName}{\textsf{#1}}}
\newcommand{\SECT}[1]{\STYLE{SectionNumber}{\textsf{#1}}}
% DECL
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\newcommand{\SEMDECL}[1]{\DECL{SemanticsName}{#1}{\SEM{#1}}}
\newcommand{\SECTDECL}[1]{\DECL{SectionNumber}{#1}{\textsf{#1}}}
% REF
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\newcommand{\SEMREF}[1]{\REF{SemanticsName}{#1}{\SEM{#1}}}
\newcommand{\SECTREF}[1]{\REF{SectionNumber}{#1}{\SECT{#1}}}
% HYPER
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\newcommand{\SECTHYPER}[3]{\HYPER{#1}{#2}{SectionNumber}{#3}{\SECT{#3}}}
% \LEFTPHRASE MATH \RIGHTPHRASE produces [[ MATH ]] with proper brackets:
\newcommand{\LEFTPHRASE}{\llbracket}
\newcommand{\RIGHTPHRASE}{\rrbracket}
% \LEFTGROUP MATH \RIGHTGROUP produces ( MATH ) where the parentheses are
% highlighted the same as keywords:
\newcommand{\LEFTGROUP}{\STYLE{Key}{(}}
\newcommand{\RIGHTGROUP}{\STYLE{Key}{)}}
% MATH\PLUS produces a superscript +
% MATH\STAR produces a superscript *
% MATH\QUERY produces a superscript ?
\newcommand{\PLUS}{{}^{\texttt{+}}}
\newcommand{\STAR}{{}^{\texttt{*}}}
\newcommand{\QUERY}{{}^{\texttt{?}}}
% \RULE{& PREMISE \\ & ...}{& FORMULA ... \\ & ...} produces an inference rule
% with separately aligned premises and conclusion
% PREMISE
% ...
% -----------
% FORMULA ...
% ...
\newcommand{\RULE}[2]
{\frac{\begin{aligned}#1\end{aligned}}{\begin{aligned}#2\end{aligned}}}
% \AXIOM{& FORMULA ... \\ & ...} produces an aligned formula
%
% FORMULA ...
% ...
\newcommand{\AXIOM}[1]{\begin{aligned}#1\end{aligned}}
% \TO TYPE produces => TYPE
\newcommand{\TO}{\mathop{\Rightarrow}}
% TERM \TRANS TERM produces TERM ---> TERM
\newcommand{\TRANS}{\longrightarrow}
% TERM \xrightarrow{LABEL} TERM puts the label above the long arrow
%
\)
IMP is considered a folklore language, without an official inventor,
and has been used in many textbooks and papers, often with slight
syntactic variations and often without being called IMP. It includes
the most basic imperative language constructs, namely basic constructs
for arithmetic and Boolean expressions, and variable assignment,
conditional, while loop and sequential composition constructs for statements.
IMP is a very small imperative language. Its CBS specification illustrates the
basic features of the framework. The start of the specification of IMP in CBS
is at IMP.