diff -r 9fa7d3890488 -r ba9297b71897 doc-src/AxClass/generated/Semigroups.tex --- a/doc-src/AxClass/generated/Semigroups.tex Tue Oct 03 18:45:36 2000 +0200 +++ b/doc-src/AxClass/generated/Semigroups.tex Tue Oct 03 18:55:23 2000 +0200 @@ -8,45 +8,40 @@ \medskip\noindent An axiomatic type class is simply a class of types that all meet certain properties, which are also called \emph{class axioms}. Thus, type classes may be also understood as type predicates - --- i.e.\ abstractions over a single type argument $\alpha$. Class + --- i.e.\ abstractions over a single type argument \isa{{\isacharprime}a}. Class axioms typically contain polymorphic constants that depend on this - type $\alpha$. These \emph{characteristic constants} behave like - operations associated with the ``carrier'' type $\alpha$. + type \isa{{\isacharprime}a}. These \emph{characteristic constants} behave like + operations associated with the ``carrier'' type \isa{{\isacharprime}a}. We illustrate these basic concepts by the following formulation of semigroups.% \end{isamarkuptext}% \isacommand{consts}\isanewline -\ \ times\ {\isacharcolon}{\isacharcolon}\ {\isachardoublequote}{\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a{\isachardoublequote}\ \ \ \ {\isacharparenleft}\isakeyword{infixl}\ {\isachardoublequote}{\isasymOtimes}{\isachardoublequote}\ \isadigit{7}\isadigit{0}{\isacharparenright}\isanewline -\isacommand{axclass}\isanewline -\ \ semigroup\ {\isacharless}\ {\isachardoublequote}term{\isachardoublequote}\isanewline -\ \ assoc{\isacharcolon}\ {\isachardoublequote}{\isacharparenleft}x\ {\isasymOtimes}\ y{\isacharparenright}\ {\isasymOtimes}\ z\ {\isacharequal}\ x\ {\isasymOtimes}\ {\isacharparenleft}y\ {\isasymOtimes}\ z{\isacharparenright}{\isachardoublequote}% +\ \ times\ {\isacharcolon}{\isacharcolon}\ {\isachardoublequote}{\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a{\isachardoublequote}\ \ \ \ {\isacharparenleft}\isakeyword{infixl}\ {\isachardoublequote}{\isasymodot}{\isachardoublequote}\ \isadigit{7}\isadigit{0}{\isacharparenright}\isanewline +\isacommand{axclass}\ semigroup\ {\isacharless}\ {\isachardoublequote}term{\isachardoublequote}\isanewline +\ \ assoc{\isacharcolon}\ {\isachardoublequote}{\isacharparenleft}x\ {\isasymodot}\ y{\isacharparenright}\ {\isasymodot}\ z\ {\isacharequal}\ x\ {\isasymodot}\ {\isacharparenleft}y\ {\isasymodot}\ z{\isacharparenright}{\isachardoublequote}% \begin{isamarkuptext}% -\noindent Above we have first declared a polymorphic constant $\TIMES - :: \alpha \To \alpha \To \alpha$ and then defined the class - $semigroup$ of all types $\tau$ such that $\TIMES :: \tau \To \tau - \To \tau$ is indeed an associative operator. The $assoc$ axiom - contains exactly one type variable, which is invisible in the above - presentation, though. Also note that free term variables (like $x$, - $y$, $z$) are allowed for user convenience --- conceptually all of - these are bound by outermost universal quantifiers. +\noindent Above we have first declared a polymorphic constant \isa{{\isasymodot}\ {\isasymColon}\ {\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a} and then defined the class \isa{semigroup} of + all types \isa{{\isasymtau}} such that \isa{{\isasymodot}\ {\isasymColon}\ {\isasymtau}\ {\isasymRightarrow}\ {\isasymtau}\ {\isasymRightarrow}\ {\isasymtau}} is indeed an + associative operator. The \isa{assoc} axiom contains exactly one + type variable, which is invisible in the above presentation, though. + Also note that free term variables (like \isa{x}, \isa{y}, \isa{z}) are allowed for user convenience --- conceptually all of these + are bound by outermost universal quantifiers. \medskip In general, type classes may be used to describe - \emph{structures} with exactly one carrier $\alpha$ and a fixed + \emph{structures} with exactly one carrier \isa{{\isacharprime}a} and a fixed \emph{signature}. Different signatures require different classes. - Below, class $plus_semigroup$ represents semigroups of the form - $(\tau, \PLUS^\tau)$, while the original $semigroup$ would correspond - to semigroups $(\tau, \TIMES^\tau)$.% + Below, class \isa{plus{\isacharunderscore}semigroup} represents semigroups of the form + \isa{{\isacharparenleft}{\isasymtau}{\isacharcomma}\ {\isasymoplus}{\isacharparenright}}, while the original \isa{semigroup} would + correspond to semigroups \isa{{\isacharparenleft}{\isasymtau}{\isacharcomma}\ {\isasymodot}{\isacharparenright}}.% \end{isamarkuptext}% \isacommand{consts}\isanewline -\ \ plus\ {\isacharcolon}{\isacharcolon}\ {\isachardoublequote}{\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a{\isachardoublequote}\ \ \ \ {\isacharparenleft}\isakeyword{infixl}\ {\isachardoublequote}{\isasymOplus}{\isachardoublequote}\ \isadigit{7}\isadigit{0}{\isacharparenright}\isanewline -\isacommand{axclass}\isanewline -\ \ plus{\isacharunderscore}semigroup\ {\isacharless}\ {\isachardoublequote}term{\isachardoublequote}\isanewline -\ \ assoc{\isacharcolon}\ {\isachardoublequote}{\isacharparenleft}x\ {\isasymOplus}\ y{\isacharparenright}\ {\isasymOplus}\ z\ {\isacharequal}\ x\ {\isasymOplus}\ {\isacharparenleft}y\ {\isasymOplus}\ z{\isacharparenright}{\isachardoublequote}% +\ \ plus\ {\isacharcolon}{\isacharcolon}\ {\isachardoublequote}{\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a\ {\isasymRightarrow}\ {\isacharprime}a{\isachardoublequote}\ \ \ \ {\isacharparenleft}\isakeyword{infixl}\ {\isachardoublequote}{\isasymoplus}{\isachardoublequote}\ \isadigit{7}\isadigit{0}{\isacharparenright}\isanewline +\isacommand{axclass}\ plus{\isacharunderscore}semigroup\ {\isacharless}\ {\isachardoublequote}term{\isachardoublequote}\isanewline +\ \ assoc{\isacharcolon}\ {\isachardoublequote}{\isacharparenleft}x\ {\isasymoplus}\ y{\isacharparenright}\ {\isasymoplus}\ z\ {\isacharequal}\ x\ {\isasymoplus}\ {\isacharparenleft}y\ {\isasymoplus}\ z{\isacharparenright}{\isachardoublequote}% \begin{isamarkuptext}% -\noindent Even if classes $plus_semigroup$ and $semigroup$ both - represent semigroups in a sense, they are certainly not quite the - same.% +\noindent Even if classes \isa{plus{\isacharunderscore}semigroup} and \isa{semigroup} both represent semigroups in a sense, they are certainly + not quite the same.% \end{isamarkuptext}% \isacommand{end}\end{isabellebody}% %%% Local Variables: