--- a/doc-src/IsarImplementation/Thy/ML.thy Fri Mar 28 11:08:18 2008 +0100
+++ b/doc-src/IsarImplementation/Thy/ML.thy Fri Mar 28 18:51:17 2008 +0100
@@ -6,24 +6,22 @@
section {* Style *}
-text FIXME
-
-text {* This style guide is loosely based on
- \url{http://caml.inria.fr/resources/doc/guides/guidelines.en.html}.
-% FIMXE \url{http://www.cs.cornell.edu/Courses/cs312/2003sp/handouts/style.htm}
-
- Like any style guide, it should not be interpreted dogmatically, but
- with care and discernment. Instead, it forms a collection of
- recommendations which, if obeyed, result in code that is not
- considered to be obfuscated. In certain cases, derivations are
- encouraged, as far as you know what you are doing.
+text {*
+ Like any style guide, also this one should not be interpreted dogmatically, but
+ with care and discernment. It consists of a collection of
+ recommendations which have been turned out useful over long years of
+ Isabelle system development and are supposed to support writing of readable
+ and managable code. Special cases encourage derivations,
+ as far as you know what you are doing.
+ \footnote{This style guide is loosely based on
+ \url{http://caml.inria.fr/resources/doc/guides/guidelines.en.html}}
\begin{description}
\item[fundamental law of programming]
Whenever writing code, keep in mind: A program is
written once, modified ten times, and read
- 100 times. So simplify its writing,
+ hundred times. So simplify its writing,
always keep future modifications in mind,
and never jeopardize readability. Every second you hesitate
to spend on making your code more clear you will
@@ -70,7 +68,7 @@
reasonable auxiliary function (if there is no
such function, very likely you got something wrong).
Any copy-and-paste will turn out to be painful
- when something has to be changed or fixed later on.
+ when something has to be changed later on.
\item[comments]
are a device which requires careful thinking before using
@@ -79,10 +77,11 @@
over efforts to explain nasty code.
\item[functional programming is based on functions]
- Avoid ``constructivisms'', i.e.\ unnecessary concrete datatype
- representations. Instead model things as abstract as
- appropriate. For example, pass a table lookup function rather
- than a concrete table with lookup performed in body. Accustom
+ Model things as abstract as appropriate. Avoid unnecessarrily
+ concrete datatype representations. For example, consider a function
+ taking some table data structure as argument and performing
+ lookups on it. Instead of taking a table, it could likewise
+ take just a lookup function. Accustom
your way of coding to the level of expressiveness a functional
programming language is giving onto you.
@@ -288,7 +287,8 @@
text {*
Beyond the proposal of the SML/NJ basis library, Isabelle comes
with its own library, from which selected parts are given here.
- See further files \emph{Pure/library.ML} and \emph{Pure/General/*.ML}.
+ These should encourage a study of the Isabelle sources,
+ in particular files \emph{Pure/library.ML} and \emph{Pure/General/*.ML}.
*}
section {* Linear transformations *}
@@ -310,29 +310,28 @@
text {*
Many problems in functional programming can be thought of
as linear transformations, i.e.~a caluclation starts with a
- particular value @{text "x \<Colon> foo"} which is then transformed
- by application of a function @{text "f \<Colon> foo \<Rightarrow> foo"},
- continued by an application of a function @{text "g \<Colon> foo \<Rightarrow> bar"},
+ particular value @{ML_text "x : foo"} which is then transformed
+ by application of a function @{ML_text "f : foo -> foo"},
+ continued by an application of a function @{ML_text "g : foo -> bar"},
and so on. As a canoncial example, take functions enriching
a theory by constant declararion and primitive definitions:
- \begin{quotation}
- @{ML "Sign.declare_const: Markup.property list -> bstring * typ * mixfix
- -> theory -> term * theory"}
-
- @{ML "Thm.add_def: bool -> bool -> bstring * term -> theory -> thm * theory"}
- \end{quotation}
+ \smallskip\begin{mldecls}
+ @{ML "Sign.declare_const: Markup.property list -> bstring * typ * mixfix
+ -> theory -> term * theory"} \\
+ @{ML "Thm.add_def: bool -> bool -> bstring * term -> theory -> thm * theory"}
+ \end{mldecls}
Written with naive application, an addition of constant
- @{text bar} with type @{typ "foo \<Rightarrow> foo"} and
+ @{term bar} with type @{typ "foo \<Rightarrow> foo"} and
a corresponding definition @{term "bar \<equiv> \<lambda>x. x"} would look like:
- \begin{quotation}
- @{ML "(fn (t, thy) => Thm.add_def false false
+ \smallskip\begin{mldecls}
+ @{ML "(fn (t, thy) => Thm.add_def false false
(\"bar_def\", Logic.mk_equals (t, @{term \"%x. x\"})) thy)
(Sign.declare_const []
(\"bar\", @{typ \"foo => foo\"}, NoSyn) thy)"}
- \end{quotation}
+ \end{mldecls}
With increasing numbers of applications, this code gets quite
unreadable. Further, it is unintuitive that things are
@@ -342,13 +341,14 @@
text {*
\noindent At this stage, Isabelle offers some combinators which allow
for more convenient notation, most notably reverse application:
- \begin{quotation}
+
+ \smallskip\begin{mldecls}
@{ML "thy
|> Sign.declare_const [] (\"bar\", @{typ \"foo => foo\"}, NoSyn)
|> (fn (t, thy) => thy
|> Thm.add_def false false
(\"bar_def\", Logic.mk_equals (t, @{term \"%x. x\"})))"}
- \end{quotation}
+ \end{mldecls}
*}
text %mlref {*
@@ -365,26 +365,29 @@
side results; to use these conveniently, yet another
set of combinators is at hand, most notably @{ML "op |->"}
which allows curried access to side results:
- \begin{quotation}
+
+ \smallskip\begin{mldecls}
@{ML "thy
|> Sign.declare_const [] (\"bar\", @{typ \"foo => foo\"}, NoSyn)
|-> (fn t => Thm.add_def false false
(\"bar_def\", Logic.mk_equals (t, @{term \"%x. x\"})))
"}
- \end{quotation}
+ \end{mldecls}
\noindent @{ML "op |>>"} allows for processing side results on their own:
- \begin{quotation}
+
+ \smallskip\begin{mldecls}
@{ML "thy
|> Sign.declare_const [] (\"bar\", @{typ \"foo => foo\"}, NoSyn)
|>> (fn t => Logic.mk_equals (t, @{term \"%x. x\"}))
|-> (fn def => Thm.add_def false false (\"bar_def\", def))
"}
- \end{quotation}
+ \end{mldecls}
\noindent Orthogonally, @{ML "op ||>"} applies a transformation
in the presence of side results which are left unchanged:
- \begin{quotation}
+
+ \smallskip\begin{mldecls}
@{ML "thy
|> Sign.declare_const [] (\"bar\", @{typ \"foo => foo\"}, NoSyn)
||> Sign.add_path \"foobar\"
@@ -392,17 +395,18 @@
(\"bar_def\", Logic.mk_equals (t, @{term \"%x. x\"})))
||> Sign.restore_naming thy
"}
- \end{quotation}
+ \end{mldecls}
- \noindent @{index_ML "op ||>>"} accumulates side results:
- \begin{quotation}
+ \noindent @{ML "op ||>>"} accumulates side results:
+
+ \smallskip\begin{mldecls}
@{ML "thy
|> Sign.declare_const [] (\"bar\", @{typ \"foo => foo\"}, NoSyn)
||>> Sign.declare_const [] (\"foobar\", @{typ \"foo => foo\"}, NoSyn)
|-> (fn (t1, t2) => Thm.add_def false false
(\"bar_def\", Logic.mk_equals (t1, t2)))
"}
- \end{quotation}
+ \end{mldecls}
*}
text %mlref {*
@@ -413,29 +417,32 @@
*}
text {*
- \noindent This principles naturally lift to @{text lists} using
+ \noindent This principles naturally lift to \emph{lists} using
the @{ML fold} and @{ML fold_map} combinators.
The first lifts a single function
- \[
- \mbox{@{text "f \<Colon> 'a -> 'b -> 'b"} to @{text "'a list -> 'b -> 'b"}}
- \]
+ \begin{quote}\footnotesize
+ @{ML_text "f : 'a -> 'b -> 'b"} to @{ML_text "'a list -> 'b -> 'b"}
+ \end{quote}
such that
- \[
- \mbox{@{text "y |> fold f [x\<^isub>1, x\<^isub>2, \<dots> x\<^isub>n] \<equiv> y |> f x\<^isub>1 |> f x\<^isub>2 |> \<dots> |> f x\<^isub>n"}}
- \]
+ \begin{quote}\footnotesize
+ @{ML_text "y |> fold f [x1, x2, ..., x_n]"} \\
+ \hspace*{2ex}@{text "\<leadsto>"} @{ML_text "y |> f x1 |> f x2 |> ... |> f x_n"}
+ \end{quote}
The second accumulates side results in a list by lifting
a single function
- \[
- \mbox{@{text "f \<Colon> 'a -> 'b -> 'c \<times> 'b"} to @{text "'a list -> 'b -> 'c list \<times> 'b"}}
- \]
+ \begin{quote}\footnotesize
+ @{ML_text "f : 'a -> 'b -> 'c * 'b"} to @{ML_text "'a list -> 'b -> 'c list * 'b"}
+ \end{quote}
such that
- \[
- \mbox{@{text "y |> fold_map f [x\<^isub>1, x\<^isub>2, \<dots> x\<^isub>n] \<equiv>"}} \\
- ~~\mbox{@{text "y |> f x\<^isub>1 ||>> f x\<^isub>2 ||>> \<dots> ||>> f x\<^isub>n ||> (fn ((z\<^isub>1, z\<^isub>2), \<dots> z\<^isub>n) => [z\<^isub>1, z\<^isub>2, \<dots> z\<^isub>n])"}}
- \]
+ \begin{quote}\footnotesize
+ @{ML_text "y |> fold_map f [x1, x2, ..., x_n]"} \\
+ \hspace*{2ex}@{text "\<leadsto>"} @{ML_text "y |> f x1 ||>> f x2 ||>> ... ||>> f x_n"} \\
+ \hspace*{6ex}@{ML_text "||> (fn ((z1, z2), ..., z_n) => [z1, z2, ..., z_n])"}
+ \end{quote}
- Example:
- \begin{quotation}
+ \noindent Example:
+
+ \smallskip\begin{mldecls}
@{ML "let
val consts = [\"foo\", \"bar\"];
in
@@ -445,9 +452,8 @@
|>> map (fn t => Logic.mk_equals (t, @{term \"%x. x\"}))
|-> (fn defs => fold_map (fn def =>
Thm.add_def false false (\"\", def)) defs)
-end
-"}
- \end{quotation}
+end"}
+ \end{mldecls}
*}
text %mlref {*
@@ -477,7 +483,7 @@
\noindent These operators allow to ``query'' a context
in a series of context transformations:
- \begin{quotation}
+ \smallskip\begin{mldecls}
@{ML "thy
|> tap (fn _ => writeln \"now adding constant\")
|> Sign.declare_const [] (\"bar\", @{typ \"foo => foo\"}, NoSyn)
@@ -487,7 +493,7 @@
else Sign.declare_const []
(\"foobar\", @{typ \"foo => foo\"}, NoSyn) #> snd)
"}
- \end{quotation}
+ \end{mldecls}
*}
section {* Options and partiality *}
@@ -508,9 +514,9 @@
text {*
Standard selector functions on @{text option}s are provided. The
@{ML try} and @{ML can} functions provide a convenient interface for
- handling exceptions -- both take as arguments a function @{text f}
- together with a parameter @{text x} and handle any exception during
- the evaluation of the application of @{text f} to @{text x}, either
+ handling exceptions -- both take as arguments a function @{ML_text f}
+ together with a parameter @{ML_text x} and handle any exception during
+ the evaluation of the application of @{ML_text f} to @{ML_text x}, either
return a lifted result (@{ML NONE} on failure) or a boolean value
(@{ML false} on failure).
*}
@@ -625,5 +631,4 @@
Most table functions correspond to those of association lists.
*}
-
end
--- a/doc-src/IsarImplementation/Thy/document/ML.tex Fri Mar 28 11:08:18 2008 +0100
+++ b/doc-src/IsarImplementation/Thy/document/ML.tex Fri Mar 28 18:51:17 2008 +0100
@@ -27,27 +27,21 @@
\isamarkuptrue%
%
\begin{isamarkuptext}%
-FIXME%
-\end{isamarkuptext}%
-\isamarkuptrue%
-%
-\begin{isamarkuptext}%
-This style guide is loosely based on
- \url{http://caml.inria.fr/resources/doc/guides/guidelines.en.html}.
-% FIMXE \url{http://www.cs.cornell.edu/Courses/cs312/2003sp/handouts/style.htm}
-
- Like any style guide, it should not be interpreted dogmatically, but
- with care and discernment. Instead, it forms a collection of
- recommendations which, if obeyed, result in code that is not
- considered to be obfuscated. In certain cases, derivations are
- encouraged, as far as you know what you are doing.
+Like any style guide, also this one should not be interpreted dogmatically, but
+ with care and discernment. It consists of a collection of
+ recommendations which have been turned out useful over long years of
+ Isabelle system development and are supposed to support writing of readable
+ and managable code. Special cases encourage derivations,
+ as far as you know what you are doing.
+ \footnote{This style guide is loosely based on
+ \url{http://caml.inria.fr/resources/doc/guides/guidelines.en.html}}
\begin{description}
\item[fundamental law of programming]
Whenever writing code, keep in mind: A program is
written once, modified ten times, and read
- 100 times. So simplify its writing,
+ hundred times. So simplify its writing,
always keep future modifications in mind,
and never jeopardize readability. Every second you hesitate
to spend on making your code more clear you will
@@ -94,7 +88,7 @@
reasonable auxiliary function (if there is no
such function, very likely you got something wrong).
Any copy-and-paste will turn out to be painful
- when something has to be changed or fixed later on.
+ when something has to be changed later on.
\item[comments]
are a device which requires careful thinking before using
@@ -103,10 +97,11 @@
over efforts to explain nasty code.
\item[functional programming is based on functions]
- Avoid ``constructivisms'', i.e.\ unnecessary concrete datatype
- representations. Instead model things as abstract as
- appropriate. For example, pass a table lookup function rather
- than a concrete table with lookup performed in body. Accustom
+ Model things as abstract as appropriate. Avoid unnecessarrily
+ concrete datatype representations. For example, consider a function
+ taking some table data structure as argument and performing
+ lookups on it. Instead of taking a table, it could likewise
+ take just a lookup function. Accustom
your way of coding to the level of expressiveness a functional
programming language is giving onto you.
@@ -322,7 +317,8 @@
\begin{isamarkuptext}%
Beyond the proposal of the SML/NJ basis library, Isabelle comes
with its own library, from which selected parts are given here.
- See further files \emph{Pure/library.ML} and \emph{Pure/General/*.ML}.%
+ These should encourage a study of the Isabelle sources,
+ in particular files \emph{Pure/library.ML} and \emph{Pure/General/*.ML}.%
\end{isamarkuptext}%
\isamarkuptrue%
%
@@ -366,29 +362,28 @@
\begin{isamarkuptext}%
Many problems in functional programming can be thought of
as linear transformations, i.e.~a caluclation starts with a
- particular value \isa{x\ {\isasymColon}\ foo} which is then transformed
- by application of a function \isa{f\ {\isasymColon}\ foo\ {\isasymRightarrow}\ foo},
- continued by an application of a function \isa{g\ {\isasymColon}\ foo\ {\isasymRightarrow}\ bar},
+ particular value \verb|x : foo| which is then transformed
+ by application of a function \verb|f : foo -> foo|,
+ continued by an application of a function \verb|g : foo -> bar|,
and so on. As a canoncial example, take functions enriching
a theory by constant declararion and primitive definitions:
- \begin{quotation}
- \verb|Sign.declare_const: Markup.property list -> bstring * typ * mixfix|\isasep\isanewline%
-\verb| -> theory -> term * theory|
-
- \verb|Thm.add_def: bool -> bool -> bstring * term -> theory -> thm * theory|
- \end{quotation}
+ \smallskip\begin{mldecls}
+ \verb|Sign.declare_const: Markup.property list -> bstring * typ * mixfix|\isasep\isanewline%
+\verb| -> theory -> term * theory| \\
+ \verb|Thm.add_def: bool -> bool -> bstring * term -> theory -> thm * theory|
+ \end{mldecls}
Written with naive application, an addition of constant
\isa{bar} with type \isa{foo\ {\isasymRightarrow}\ foo} and
- a corresponding definition \isa{bar{\isasymColon}{\isacharprime}a{\isasymColon}{\isacharbraceleft}{\isacharbraceright}\ {\isasymRightarrow}\ {\isacharprime}a{\isasymColon}{\isacharbraceleft}{\isacharbraceright}\ {\isasymequiv}\ {\isasymlambda}x{\isasymColon}{\isacharprime}a{\isasymColon}{\isacharbraceleft}{\isacharbraceright}{\isachardot}\ x} would look like:
+ a corresponding definition \isa{bar\ {\isasymequiv}\ {\isasymlambda}x{\isachardot}\ x} would look like:
- \begin{quotation}
- \verb|(fn (t, thy) => Thm.add_def false false|\isasep\isanewline%
+ \smallskip\begin{mldecls}
+ \verb|(fn (t, thy) => Thm.add_def false false|\isasep\isanewline%
\verb| ("bar_def", Logic.mk_equals (t, @{term "%x. x"})) thy)|\isasep\isanewline%
\verb| (Sign.declare_const []|\isasep\isanewline%
\verb| ("bar", @{typ "foo => foo"}, NoSyn) thy)|
- \end{quotation}
+ \end{mldecls}
With increasing numbers of applications, this code gets quite
unreadable. Further, it is unintuitive that things are
@@ -399,13 +394,14 @@
\begin{isamarkuptext}%
\noindent At this stage, Isabelle offers some combinators which allow
for more convenient notation, most notably reverse application:
- \begin{quotation}
+
+ \smallskip\begin{mldecls}
\verb|thy|\isasep\isanewline%
\verb||\verb,|,\verb|> Sign.declare_const [] ("bar", @{typ "foo => foo"}, NoSyn)|\isasep\isanewline%
\verb||\verb,|,\verb|> (fn (t, thy) => thy|\isasep\isanewline%
\verb||\verb,|,\verb|> Thm.add_def false false|\isasep\isanewline%
\verb| ("bar_def", Logic.mk_equals (t, @{term "%x. x"})))|
- \end{quotation}%
+ \end{mldecls}%
\end{isamarkuptext}%
\isamarkuptrue%
%
@@ -437,26 +433,29 @@
side results; to use these conveniently, yet another
set of combinators is at hand, most notably \verb|op |\verb,|,\verb|->|
which allows curried access to side results:
- \begin{quotation}
+
+ \smallskip\begin{mldecls}
\verb|thy|\isasep\isanewline%
\verb||\verb,|,\verb|> Sign.declare_const [] ("bar", @{typ "foo => foo"}, NoSyn)|\isasep\isanewline%
\verb||\verb,|,\verb|-> (fn t => Thm.add_def false false|\isasep\isanewline%
\verb| ("bar_def", Logic.mk_equals (t, @{term "%x. x"})))|\isasep\isanewline%
- \end{quotation}
+ \end{mldecls}
\noindent \verb|op |\verb,|,\verb|>>| allows for processing side results on their own:
- \begin{quotation}
+
+ \smallskip\begin{mldecls}
\verb|thy|\isasep\isanewline%
\verb||\verb,|,\verb|> Sign.declare_const [] ("bar", @{typ "foo => foo"}, NoSyn)|\isasep\isanewline%
\verb||\verb,|,\verb|>> (fn t => Logic.mk_equals (t, @{term "%x. x"}))|\isasep\isanewline%
\verb||\verb,|,\verb|-> (fn def => Thm.add_def false false ("bar_def", def))|\isasep\isanewline%
- \end{quotation}
+ \end{mldecls}
\noindent Orthogonally, \verb|op |\verb,|,\verb||\verb,|,\verb|>| applies a transformation
in the presence of side results which are left unchanged:
- \begin{quotation}
+
+ \smallskip\begin{mldecls}
\verb|thy|\isasep\isanewline%
\verb||\verb,|,\verb|> Sign.declare_const [] ("bar", @{typ "foo => foo"}, NoSyn)|\isasep\isanewline%
\verb||\verb,|,\verb||\verb,|,\verb|> Sign.add_path "foobar"|\isasep\isanewline%
@@ -464,17 +463,18 @@
\verb| ("bar_def", Logic.mk_equals (t, @{term "%x. x"})))|\isasep\isanewline%
\verb||\verb,|,\verb||\verb,|,\verb|> Sign.restore_naming thy|\isasep\isanewline%
- \end{quotation}
+ \end{mldecls}
- \noindent \indexml{op ||$>$$>$}\verb|op |\verb,|,\verb||\verb,|,\verb|>>| accumulates side results:
- \begin{quotation}
+ \noindent \verb|op |\verb,|,\verb||\verb,|,\verb|>>| accumulates side results:
+
+ \smallskip\begin{mldecls}
\verb|thy|\isasep\isanewline%
\verb||\verb,|,\verb|> Sign.declare_const [] ("bar", @{typ "foo => foo"}, NoSyn)|\isasep\isanewline%
\verb||\verb,|,\verb||\verb,|,\verb|>> Sign.declare_const [] ("foobar", @{typ "foo => foo"}, NoSyn)|\isasep\isanewline%
\verb||\verb,|,\verb|-> (fn (t1, t2) => Thm.add_def false false|\isasep\isanewline%
\verb| ("bar_def", Logic.mk_equals (t1, t2)))|\isasep\isanewline%
- \end{quotation}%
+ \end{mldecls}%
\end{isamarkuptext}%
\isamarkuptrue%
%
@@ -500,29 +500,32 @@
\endisadelimmlref
%
\begin{isamarkuptext}%
-\noindent This principles naturally lift to \isa{lists} using
+\noindent This principles naturally lift to \emph{lists} using
the \verb|fold| and \verb|fold_map| combinators.
The first lifts a single function
- \[
- \mbox{\isa{f\ {\isasymColon}\ {\isacharprime}a\ {\isacharminus}{\isachargreater}\ {\isacharprime}b\ {\isacharminus}{\isachargreater}\ {\isacharprime}b} to \isa{{\isacharprime}a\ list\ {\isacharminus}{\isachargreater}\ {\isacharprime}b\ {\isacharminus}{\isachargreater}\ {\isacharprime}b}}
- \]
+ \begin{quote}\footnotesize
+ \verb|f : 'a -> 'b -> 'b| to \verb|'a list -> 'b -> 'b|
+ \end{quote}
such that
- \[
- \mbox{\isa{y\ {\isacharbar}{\isachargreater}\ fold\ f\ {\isacharbrackleft}x\isactrlisub {\isadigit{1}}{\isacharcomma}\ x\isactrlisub {\isadigit{2}}{\isacharcomma}\ {\isasymdots}\ x\isactrlisub n{\isacharbrackright}\ {\isasymequiv}\ y\ {\isacharbar}{\isachargreater}\ f\ x\isactrlisub {\isadigit{1}}\ {\isacharbar}{\isachargreater}\ f\ x\isactrlisub {\isadigit{2}}\ {\isacharbar}{\isachargreater}\ {\isasymdots}\ {\isacharbar}{\isachargreater}\ f\ x\isactrlisub n}}
- \]
+ \begin{quote}\footnotesize
+ \verb|y |\verb,|,\verb|> fold f [x1, x2, ..., x_n]| \\
+ \hspace*{2ex}\isa{{\isasymleadsto}} \verb|y |\verb,|,\verb|> f x1 |\verb,|,\verb|> f x2 |\verb,|,\verb|> ... |\verb,|,\verb|> f x_n|
+ \end{quote}
The second accumulates side results in a list by lifting
a single function
- \[
- \mbox{\isa{f\ {\isasymColon}\ {\isacharprime}a\ {\isacharminus}{\isachargreater}\ {\isacharprime}b\ {\isacharminus}{\isachargreater}\ {\isacharprime}c\ {\isasymtimes}\ {\isacharprime}b} to \isa{{\isacharprime}a\ list\ {\isacharminus}{\isachargreater}\ {\isacharprime}b\ {\isacharminus}{\isachargreater}\ {\isacharprime}c\ list\ {\isasymtimes}\ {\isacharprime}b}}
- \]
+ \begin{quote}\footnotesize
+ \verb|f : 'a -> 'b -> 'c * 'b| to \verb|'a list -> 'b -> 'c list * 'b|
+ \end{quote}
such that
- \[
- \mbox{\isa{y\ {\isacharbar}{\isachargreater}\ fold{\isacharunderscore}map\ f\ {\isacharbrackleft}x\isactrlisub {\isadigit{1}}{\isacharcomma}\ x\isactrlisub {\isadigit{2}}{\isacharcomma}\ {\isasymdots}\ x\isactrlisub n{\isacharbrackright}\ {\isasymequiv}}} \\
- ~~\mbox{\isa{y\ {\isacharbar}{\isachargreater}\ f\ x\isactrlisub {\isadigit{1}}\ {\isacharbar}{\isacharbar}{\isachargreater}{\isachargreater}\ f\ x\isactrlisub {\isadigit{2}}\ {\isacharbar}{\isacharbar}{\isachargreater}{\isachargreater}\ {\isasymdots}\ {\isacharbar}{\isacharbar}{\isachargreater}{\isachargreater}\ f\ x\isactrlisub n\ {\isacharbar}{\isacharbar}{\isachargreater}\ {\isacharparenleft}fn\ {\isacharparenleft}{\isacharparenleft}z\isactrlisub {\isadigit{1}}{\isacharcomma}\ z\isactrlisub {\isadigit{2}}{\isacharparenright}{\isacharcomma}\ {\isasymdots}\ z\isactrlisub n{\isacharparenright}\ {\isacharequal}{\isachargreater}\ {\isacharbrackleft}z\isactrlisub {\isadigit{1}}{\isacharcomma}\ z\isactrlisub {\isadigit{2}}{\isacharcomma}\ {\isasymdots}\ z\isactrlisub n{\isacharbrackright}{\isacharparenright}}}
- \]
+ \begin{quote}\footnotesize
+ \verb|y |\verb,|,\verb|> fold_map f [x1, x2, ..., x_n]| \\
+ \hspace*{2ex}\isa{{\isasymleadsto}} \verb|y |\verb,|,\verb|> f x1 |\verb,|,\verb||\verb,|,\verb|>> f x2 |\verb,|,\verb||\verb,|,\verb|>> ... |\verb,|,\verb||\verb,|,\verb|>> f x_n| \\
+ \hspace*{6ex}\verb||\verb,|,\verb||\verb,|,\verb|> (fn ((z1, z2), ..., z_n) => [z1, z2, ..., z_n])|
+ \end{quote}
- Example:
- \begin{quotation}
+ \noindent Example:
+
+ \smallskip\begin{mldecls}
\verb|let|\isasep\isanewline%
\verb| val consts = ["foo", "bar"];|\isasep\isanewline%
\verb|in|\isasep\isanewline%
@@ -532,9 +535,8 @@
\verb| |\verb,|,\verb|>> map (fn t => Logic.mk_equals (t, @{term "%x. x"}))|\isasep\isanewline%
\verb| |\verb,|,\verb|-> (fn defs => fold_map (fn def =>|\isasep\isanewline%
\verb| Thm.add_def false false ("", def)) defs)|\isasep\isanewline%
-\verb|end|\isasep\isanewline%
-
- \end{quotation}%
+\verb|end|
+ \end{mldecls}%
\end{isamarkuptext}%
\isamarkuptrue%
%
@@ -594,7 +596,7 @@
\noindent These operators allow to ``query'' a context
in a series of context transformations:
- \begin{quotation}
+ \smallskip\begin{mldecls}
\verb|thy|\isasep\isanewline%
\verb||\verb,|,\verb|> tap (fn _ => writeln "now adding constant")|\isasep\isanewline%
\verb||\verb,|,\verb|> Sign.declare_const [] ("bar", @{typ "foo => foo"}, NoSyn)|\isasep\isanewline%
@@ -604,7 +606,7 @@
\verb| else Sign.declare_const []|\isasep\isanewline%
\verb| ("foobar", @{typ "foo => foo"}, NoSyn) #> snd)|\isasep\isanewline%
- \end{quotation}%
+ \end{mldecls}%
\end{isamarkuptext}%
\isamarkuptrue%
%
@@ -642,9 +644,9 @@
\begin{isamarkuptext}%
Standard selector functions on \isa{option}s are provided. The
\verb|try| and \verb|can| functions provide a convenient interface for
- handling exceptions -- both take as arguments a function \isa{f}
- together with a parameter \isa{x} and handle any exception during
- the evaluation of the application of \isa{f} to \isa{x}, either
+ handling exceptions -- both take as arguments a function \verb|f|
+ together with a parameter \verb|x| and handle any exception during
+ the evaluation of the application of \verb|f| to \verb|x|, either
return a lifted result (\verb|NONE| on failure) or a boolean value
(\verb|false| on failure).%
\end{isamarkuptext}%