fpom · August 4, 2023 02:05 · cdlm · Jan 25, 2020 · fpom · Jan 25, 2020
diff --git a/anim.py b/anim.py
 import collections
 from inspect import Signature, Parameter, cleandoc
 from pygments import highlight as _pygmentize
 import pygments.lexers, pygments.formatters

 ##
 ## code pretty-printing
 ##

 _lexer = pygments.lexers.get_lexer_by_name("C")
 _formatter = pygments.formatters.get_formatter_by_name("latex")

 def pygmentize (src) :
    return "\n".join("\n".join(_pygmentize(line, _lexer, _formatter).splitlines()[1:-1])
                     for line in src.split("\n"))

 ##
 ## simulation environment
 ##

 class Env (dict) :
    def __init__ (self, *l, **k) :
        super().__init__(*l, **k)
    def __setitem__ (self, key, val) :
        old = self.get(key, None)
        if isinstance(old, Value) :
            old.set(val)
        else :
            super().__setitem__(key, val)
    def __getitem__ (self, key) :
        old = self.get(key, None)
        if isinstance(old, Value) :
            return old.get()
        else :
            return super().__getitem__(key)

 class CAni (object) :
    _env = Env()
    @property
    def IP (self) :
        return self._env.get("IP", 1)
    @IP.setter
    def IP (self, val) :
        self._env["IP"] = val

 class Anim (object) :
    def __init__ (self) :
        self.steps = collections.defaultdict(list)
    def __getitem__ (self, key) :
        return self.steps[key]
    def range_iter (self) :
        last_step, last_info = None, None
        for step, info in sorted(self.steps.items()) :
            if last_step is None :
                last_step, last_info = step, info
            elif last_info == info :
                pass
            else :
                yield last_step, step-1, last_info
                last_step, last_info = step, info
        yield last_step, step, last_info
    def steps_iter (self) :
        inv = collections.defaultdict(set)
        for step, info in self.steps.items() :
            inv[tuple(info)].add(step)
        def minstep (item) :
            return tuple(sorted(item[1]))
        for info, steps in sorted(inv.items(), key=minstep) :
            yield list(sorted(steps)), list(info)

 ##
 ## data structures
 ##

 class Value (CAni) :
    def __init__ (self, init=None) :
        self.hist = [[init, self.IP, None]]
        self.show = set()
    def get (self) :
        self.show.add(self.IP)
        return self.hist[-1][0]
    def set (self, val) :
        self.show.add(self.IP)
        if self.IP == self.hist[-1][1] :
            self.hist[-1][0] = val
        else :
            self.hist[-1][2] = self.IP-1
            self.hist.append([val, self.IP, None])
    def stop (self) :
        self.hist[-1][2] = self.IP-1
    def tex (self, w=1, h=1, x=0, y=0) :
        tpl = r"""\coordinate ({id}) at ({_x},{y});
        \draw[very thick,opacity=0] ({_x},{_y}) rectangle ++({w},{h});
        \draw ({_x},{_y}) rectangle ++({w},{h});
        {access}%% values
        {states}
        """
        self.stop()
        if self.show :
            access = cleandoc(r"""\only<{access}>{{
            \draw[very thick,blue!50!black,fill=blue!20] ({_x},{_y}) rectangle ++({w},{h});
            }}
            """).format(w=w, h=h, x=x, y=y, _x=x-.5*w, _y=y-.5*h,
                        access=",".join(str(s) for s in sorted(self.show)))
        else :
            access = ""
        return cleandoc(tpl).format(w=w, h=h, x=x, y=y, _x=x-.5*w, _y=y-.5*h,
                                    id=self.ptrto(),
                                    access=access,
                                    states="\n".join(self._states(x, y)))
    def ptrto (self) :
        return str(id(self)).replace("-", "_")
    def _states (self, x, y) :
        for value, start, stop in self.hist :
            if value is not None :
                yield (r"\only<{start}-{stop}>{{ {state} }}"
                       r"").format(start=start or 1,
                                   stop=stop or "",
                                   state=self.tex_state(value, x, y))
    def tex_state (self, value, x, y) :
        return f"\\node at ({x},{y}) {{{value}}};"

 class Pointer (Value) :
    def __init__ (self, init=None) :
        super().__init__(init)
    def tex_state (self, value, x, y) :
        return cleandoc(r"""\draw[thick,-latex] ({x},{y}) -- ({tgt});
                            \node[fill,circle,inner sep=1.5pt] at ({x},{y}) {{}};"""
                        "").format(x=x, y=y, tgt=value.ptrto())

 class Array (CAni) :
    def __init__ (self, init, index=[]) :
        self.idx = {}
        if isinstance(init, int) :
            data = [None] * init
        else :
            data = list(init)
        self.data = [Value(v) for v in data]
        for name in index :
            self.index(name)
    def index (self, name, init=None) :
        self.idx[name] = self._env[name] = Value(init)
    def ptrto (self) :
        return str(id(self)).replace("-", "_")
    def __len__ (self) :
        return len(self.data)
    def __getitem__ (self, idx) :
        return self.data[idx].get()
    def __setitem__ (self, idx, val) :
        self.data[idx].set(val)
    def tex (self, w=1, h=1) :
        tpl = r"""%% array grid
        \begin{{scope}}[shift={{(-.5,-.5)}}]
        \coordinate ({id}) at (0,.5);
          \draw[very thick,opacity=0] (0,0) grid ({len},1);
          \draw (0,0) grid ({len},1);
        \end{{scope}}
        \foreach \x in {{0,...,{len_1}}} {{
          \node[below] at (\x,-.5) {{\relsize{{-2}}\color{{gray}}\texttt{{\x}}}};
        }}
        %% index
        {index}
        %% access
        {access}
        %% values
        {states}
        """
        return cleandoc(tpl).format(len=len(self),
                                    len_1=len(self) - 1,
                                    id=self.ptrto(),
                                    index="\n".join(self._index()),
                                    access="\n".join(self._access()),
                                    states="\n".join(self._states()))
    def _index (self) :
        anim = Anim()
        for name, cell in self.idx.items() :
            cell.stop()
            for value, start, stop in cell.hist :
                for step in range(start, stop+1) :
                    anim[step].append((name, value))
        for start, stop, info in anim.range_iter() :
            xpos = collections.defaultdict(list)
            for name, value in info :
                if value is not None :
                    xpos[value].append(name)
            if not xpos :
                continue
            yield (r"\uncover<{start}-{stop}>{{"
                   r"").format(start=start, stop=stop)
            for value, names in xpos.items() :
                yield (r"  \node[above] at ({xpos},.5) {{\texttt{{{label}}}}};"
                       r"").format(xpos=value, label=",".join(names))
            yield "}"
    def _access (self) :
        anim = Anim()
        for pos, cell in enumerate(self.data) :
            cell.stop()
            for step in cell.show :
                anim[step].append(pos)
        for steps, info in anim.steps_iter() :
            yield (r"\only<{steps}>{{"
                   r"").format(steps=",".join(str(s) for s in steps))
            for pos in info :
                yield (r"  \draw[very thick,blue!50!black,fill=blue!20] "
                       r"({x},-.5) rectangle ++(1,1);"
                       r"").format(x=pos-.5)
            yield "}"
    def _states (self) :
        anim = collections.defaultdict(list)
        for pos, cell in enumerate(self.data) :
            cell.stop()
            for value, start, stop in cell.hist :
                anim[start,stop].append((pos, value))
        def firstlargest (item) :
            return (item[0][0], -item[0][1])
        for (start, stop), info in sorted(anim.items(), key=firstlargest) :
            yield (r"\only<{start}-{stop}>{{"
                   r"").format(start=start, stop=stop)
            for pos, value in info :
                yield r"  \node at ({x},0) {{{val}}};".format(x=pos, val=value)
            yield "}"

 class Struct (CAni) :
    def __init__ (self, **members) :
        self.__dict__["_members"] = dict(members)
    def __getattr__ (self, name) :
        if name in self._members :
            return self._members[name].get()
        else :
            return super().__getattr__(name)
    def __setattr__ (self, name, value) :
        if name in self._members :
            self._members[name].set(value)
        else :
            super.__setattr__(name, value)
    def tex (self, w=1, h=1) :
        return "\n".join(self._tex(w, h))
    def _tex (self, w, h) :
        pos = (len(self._members) - 1) * h
        for name, cell in self._members.items() :
            yield f"%% .{name}"
            yield cell.tex(w=w, h=h, x=0, y=pos)
            yield r"\node[left] at ({pos}) {{.{name}}};".format(pos=cell.ptrto(),
                                                                name=name)
            pos -= h

 class Data (CAni) :
    def __init__ (self, *content) :
        self.content = list(content)
    def tex (self, *args) :
        return "\n".join(self._tex(args))
    def _tex (self, args) :
        args = list(args)
        args.extend({} for i in range(len(self.content) - len(args)))
        for a, d in zip(args, self.content) :
            yield r"\begin{{scope}}[{args}]".format(args=",".join("%s=%s" % i
                                                                  for i in a.items()))
            for line in d.tex().splitlines() :
                yield "  " + line
            yield r"\end{scope}"

 ##
 ## code blocks
 ##

 class _CODE (CAni) :
    _fields = []
    _options = []
    def __init__ (self, *l, **k) :
        params = []
        for i, name in enumerate(self._fields) :
            if name[0] == "*" :
                self._fields = self._fields[:]
                self._fields[i] = name[1:]
                params.append(Parameter(name[1:], Parameter.VAR_POSITIONAL))
            else :
                params.append(Parameter(name, Parameter.POSITIONAL_OR_KEYWORD))
        for name in self._options :
            params.append(Parameter(name, Parameter.POSITIONAL_OR_KEYWORD, default=None))
        params.append(Parameter("src", Parameter.KEYWORD_ONLY, default=None))
        sig = Signature(params)
        args = sig.bind(*l, **k)
        args.apply_defaults()
        for key, val in args.arguments.items() :
            setattr(self, key, val)
        self._at = set()
    @property
    def last (self) :
        return self._env.get("LAST", None)
    def __str__ (self) :
        content = []
        for key, val in self.items() :
            if isinstance(val, _CODE) :
                content.append((key, str(val)))
            else :
                content.append((key, repr(val)))
        return "%s(%s)" % (self.__class__.__name__,
                           ", ".join("%s=%r" % item for item in content))
    def items (self) :
        for field in self._fields :
            yield field, getattr(self, field)
        for field in self._options :
            member = getattr(self, field, None)
            if member is not None :
                yield field, member
    def source (self) :
        sub = {}
        for key, val in self.items() :
            if isinstance(val, _CODE) :
                sub[key] = val.source()
            else :
                sub[key] = val
        return self.src.format(**sub)
    def tex (self) :
        sub = self.src.format(**{key : "$" for key, val in self.items()}).split("$")
        parts = [pygmentize(sub[0])]
        for (key, val), txt in zip(self.items(), sub[1:]) :
            if isinstance(val, _CODE) :
                parts.append(val.tex())
            else :
                parts.append(pygmentize(str(val)))
            parts.append(pygmentize(txt))
        tex = "".join(parts)
        if self._at :
            return r"\onlyhl{%s}{" % ",".join(str(i) for i in self._at) + tex + "}"
        else :
            return tex

 class BLOCK (_CODE) :
    _fields = ["*body"]
    def __call__ (self) :
        self._at.add(self.IP)
        for code in self.body :
            code()
    def source (self) :
        return "".join(b.source() for b in self.body)
    def tex (self) :
        return "".join(b.tex() for b in self.body)

 class STMT (_CODE) :
    _fields = ["*steps"]
    def __call__ (self) :
        for s in self.steps :
            self._at.add(self.IP)
            exec(s, self._env, self._env)
            self.IP += 1

 class EXPR (_CODE) :
    _fields = ["expr"]
    def __init__ (self, *l, **k) :
        super().__init__(*l, **k)
        if self.src is None :
            self.src = self.expr
    def __call__ (self) :
        self._at.add(self.IP)
        self._env["LAST"] = eval(self.expr, self._env, self._env)
        self.IP += 1

 class PY (_CODE) :
    _fields = ["py"]
    def __call__ (self) :
        exec(self.py, self._env)
    def tex (self) :
        return ""
    def source (self) :
        return ""

 class ENV (_CODE) :
    _fields = ["name", "value"]
    def __call__ (self) :
        self._env[self.name] = self.value
    def tex (self) :
        return ""
    def source (self) :
        return ""

 class WS (_CODE) :
    _fields = []
    def __init__ (self, src) :
        super().__init__(src=src)
    def __call__ (self) :
        pass
    def tex (self) :
        return self.src

 class DECL (_CODE) :
    _fields = ["name"]
    _options = ["init", "animate"]
    def __init__ (self, *l, **k) :
        super().__init__(*l, **k)
        if self.animate is not None :
            self._cell = self._env[self.name] = Value()
    def __call__ (self) :
        if self.init is not None :
            self.init()
            self._env[self.name] = self.last
        else :
            self._env[self.name] = None
        self._at.add(self.IP)
        self.IP += 1
    def tex (self) :
        src = super().tex()
        if self.animate is None :
            return src
        else :
            return src + "  " + "".join(self._tex())
    def _tex (self) :
        tail = r"\PY{{c+c1}}{{/* {value} */}}"
        for value, start, stop in self._cell.hist :
            if value is not None :
                yield (r"\onlyshow{{{start}-{stop}}}{{{value}}}"
                       r"").format(start=start or 1,
                                   stop=stop or "",
                                   value=tail.format(value=value))

 class BreakLoop (Exception) :
    def __init__ (self) :
        super().__init__()

 class BREAK (_CODE) :
    def __call__ (self) :
        self._at.add(self.IP)
        self.IP += 1
        raise BreakLoop()

 class FunctionReturn (Exception) :
    def __init__ (self, RET) :
        super().__init__()
        self.RET = RET

 class RETURN (_CODE) :
    _fields = ["value"]
    def __call__ (self) :
        self.value()
        self._at.add(self.IP)
        self.IP += 1
        raise FunctionReturn(self.last)

 class IF (_CODE) :
    _fields = ["cond", "then"]
    _options = ["otherwise"]
    def __call__ (self) :
        self.cond()
        if self.last :
            self.then()
        elif self.otherwise is not None :
            self.otherwise()

 class WHILE (_CODE) :
    _fields = ["cond", "body"]
    def __call__ (self) :
        try :
            while True :
                self.cond()
                if not self.last :
                    break
                self.body()
        except BreakLoop :
            return

 class DO (_CODE) :
    _fields = ["body", "cond"]
    def __call__ (self) :
        try :
            while True :
                self.body()
                self.cond()
                if not self.last :
                    break
        except BreakLoop :
            pass

 class FOR (_CODE) :
    _fields = ["init", "cond", "step", "body"]
    def __call__ (self) :
        self.init()
        try :
            while True :
                self.cond()
                if not self.last :
                    break
                self.body()
                self.step()
        except BreakLoop :
            pass

 class FUNC (_CODE) :
    _fields = ["body"]
    def __call__ (self) :
        try :
            self.body()
        except FunctionReturn as exc :
            self._env["LAST"] = exc.RET
diff --git a/LICENCE b/LICENCE
                   GNU LESSER GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.


  This version of the GNU Lesser General Public License incorporates
 the terms and conditions of version 3 of the GNU General Public
 License, supplemented by the additional permissions listed below.

  0. Additional Definitions.

  As used herein, "this License" refers to version 3 of the GNU Lesser
 General Public License, and the "GNU GPL" refers to version 3 of the GNU
 General Public License.

  "The Library" refers to a covered work governed by this License,
 other than an Application or a Combined Work as defined below.

  An "Application" is any work that makes use of an interface provided
 by the Library, but which is not otherwise based on the Library.
 Defining a subclass of a class defined by the Library is deemed a mode
 of using an interface provided by the Library.

  A "Combined Work" is a work produced by combining or linking an
 Application with the Library.  The particular version of the Library
 with which the Combined Work was made is also called the "Linked
 Version".

  The "Minimal Corresponding Source" for a Combined Work means the
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 object code and/or source code for the Application, including any data
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 Application, but excluding the System Libraries of the Combined Work.

  1. Exception to Section 3 of the GNU GPL.

  You may convey a covered work under sections 3 and 4 of this License
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   function or data, the facility still operates, and performs
   whatever part of its purpose remains meaningful, or

   b) under the GNU GPL, with none of the additional permissions of
   this License applicable to that copy.

  3. Object Code Incorporating Material from Library Header Files.

  The object code form of an Application may incorporate material from
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diff --git a/quicksort.py b/quicksort.py
 from anim import *

 ##
 ## quicksort partitioning
 ##

 array = Array([3, 13, 5, 0, 7, 11, 4, 9, 14, 2, 10, 1, 12, 8, 6],
              index=["a", "b"])
 tab = Struct(len=Value(15),
             val=Pointer(array))

 partition = FUNC(BLOCK(ENV("t", tab),
                       WS("  "),
                       DECL("pivot", EXPR("t.val[(t.len-1)//2]",
                                          src="t.val[(t.len-1)/2]"),
                            animate=True,
                            src="int {name} = {init};"),
                       WS("\n  "),
                       DECL("a", EXPR("-1"),
                            src="uint {name} = {init};"),
                       WS("\n  "),
                       DECL("b", EXPR("t.len"),
                            src="uint {name} = {init};"),
                       WS("\n  "),
                       WHILE(EXPR("1", src="1"),
                             BLOCK(WS("    "),
                                   DO(STMT("a+=1", src="a++;"),
                                      EXPR("t.val[a] < pivot"),
                                      src="do {{ {body} }} while ({cond});"),
                                   WS("\n    "),
                                   DO(STMT("b-=1", src="b--;"),
                                      EXPR("t.val[b] > pivot"),
                                      src="do {{ {body} }} while ({cond});"),
                                   WS("\n    "),
                                   IF(EXPR("a >= b"),
                                      RETURN(EXPR("b"),
                                             src="return {value};"),
                                      src="if ({cond}) {{ {then} }}"),
                                   WS("\n     "),
                                   STMT("_old = t.val[a], t.val[b]",
                                        "t.val[b], t.val[a] = _old",
                                        src="swap(t, a, b);"),
                                   WS("\n")),
                             src="while ({cond}) {{\n{body}  }}"),
                       WS("\n")),
                 src="uint partition (Tab t) {{\n{body}}}\n")

 # run code and save its animation
 partition.IP += 1
 partition()
 with open("code.tex", "w") as out :
    out.write(partition.tex())

 # save data anaimation
 data = Data(array, tab)
 with open("code.tikz", "w") as out :
    out.write(data.tex({"shift": "{(2.5,0)}"}, {}))
diff --git a/test.sh b/test.sh
 python quicksort.py
 pdflatex test
 pdflatex test
diff --git a/test.tex b/test.tex
 \documentclass{beamer}

 \usepackage[francais]{babel}
 \usepackage[utf8x]{inputenc}
 \usepackage[T1]{fontenc}
 \usepackage{ae}
 \usepackage{tikz}
 \usepackage{adjustbox}
 \usepackage{fancyvrb}
 \usepackage{pygments}
 \usepackage{relsize}

 \usetikzlibrary{arrows}

 \def\hl #1{{\setbox0=\hbox{#1}%
    \adjustbox{set vsize={\ht0}{\dp0}}{\hbox to \wd0{\hss\colorbox{yellow}{#1}\hss}}}}

 \def\hl #1{%
  \tikz[overlay,baseline,inner sep=1pt]
    \node[fill=yellow,anchor=text] {\color{yellow}#1};%
  #1%
 }%

 \def\onlyhl #1{\only<#1>\hl}
 \def\onlyshow #1{\only<#1>}

 \begin{document}

 \begin{frame}[fragile]{Tri rapide: algorithme de partitionnement}
  \VerbatimInput[commandchars=\\\{\}]{code.tex}
  \begin{tikzpicture}[scale=.55]
    \input{code.tikz}
  \end{tikzpicture}
 \end{frame}

 \end{document}
	import collections
	from inspect import Signature, Parameter, cleandoc
	from pygments import highlight as _pygmentize
	import pygments.lexers, pygments.formatters

	##
	## code pretty-printing
	##

	_lexer = pygments.lexers.get_lexer_by_name("C")
	_formatter = pygments.formatters.get_formatter_by_name("latex")

	def pygmentize (src) :
	return "\n".join("\n".join(_pygmentize(line, _lexer, _formatter).splitlines()[1:-1])
	for line in src.split("\n"))

	##
	## simulation environment
	##

	class Env (dict) :
	def __init__ (self, l, *k) :
	super().__init__(l, *k)
	def __setitem__ (self, key, val) :
	old = self.get(key, None)
	if isinstance(old, Value) :
	old.set(val)
	else :
	super().__setitem__(key, val)
	def __getitem__ (self, key) :
	old = self.get(key, None)
	if isinstance(old, Value) :
	return old.get()
	else :
	return super().__getitem__(key)

	class CAni (object) :
	_env = Env()
	@property
	def IP (self) :
	return self._env.get("IP", 1)
	@IP.setter
	def IP (self, val) :
	self._env["IP"] = val

	class Anim (object) :
	def __init__ (self) :
	self.steps = collections.defaultdict(list)
	def __getitem__ (self, key) :
	return self.steps[key]
	def range_iter (self) :
	last_step, last_info = None, None
	for step, info in sorted(self.steps.items()) :
	if last_step is None :
	last_step, last_info = step, info
	elif last_info == info :
	pass
	else :
	yield last_step, step-1, last_info
	last_step, last_info = step, info
	yield last_step, step, last_info
	def steps_iter (self) :
	inv = collections.defaultdict(set)
	for step, info in self.steps.items() :
	inv[tuple(info)].add(step)
	def minstep (item) :
	return tuple(sorted(item[1]))
	for info, steps in sorted(inv.items(), key=minstep) :
	yield list(sorted(steps)), list(info)

	##
	## data structures
	##

	class Value (CAni) :
	def __init__ (self, init=None) :
	self.hist = [[init, self.IP, None]]
	self.show = set()
	def get (self) :
	self.show.add(self.IP)
	return self.hist[-1][0]
	def set (self, val) :
	self.show.add(self.IP)
	if self.IP == self.hist[-1][1] :
	self.hist[-1][0] = val
	else :
	self.hist[-1][2] = self.IP-1
	self.hist.append([val, self.IP, None])
	def stop (self) :
	self.hist[-1][2] = self.IP-1
	def tex (self, w=1, h=1, x=0, y=0) :
	tpl = r"""\coordinate ({id}) at ({_x},{y});
	\draw[very thick,opacity=0] ({_x},{_y}) rectangle ++({w},{h});
	\draw ({_x},{_y}) rectangle ++({w},{h});
	{access}%% values
	{states}
	"""
	self.stop()
	if self.show :
	access = cleandoc(r"""\only<{access}>{{
	\draw[very thick,blue!50!black,fill=blue!20] ({_x},{_y}) rectangle ++({w},{h});
	}}
	""").format(w=w, h=h, x=x, y=y, _x=x-.5w, _y=y-.5h,
	access=",".join(str(s) for s in sorted(self.show)))
	else :
	access = ""
	return cleandoc(tpl).format(w=w, h=h, x=x, y=y, _x=x-.5w, _y=y-.5h,
	id=self.ptrto(),
	access=access,
	states="\n".join(self._states(x, y)))
	def ptrto (self) :
	return str(id(self)).replace("-", "_")
	def _states (self, x, y) :
	for value, start, stop in self.hist :
	if value is not None :
	yield (r"\only<{start}-{stop}>{{ {state} }}"
	r"").format(start=start or 1,
	stop=stop or "",
	state=self.tex_state(value, x, y))
	def tex_state (self, value, x, y) :
	return f"\\node at ({x},{y}) {{{value}}};"

	class Pointer (Value) :
	def __init__ (self, init=None) :
	super().__init__(init)
	def tex_state (self, value, x, y) :
	return cleandoc(r"""\draw[thick,-latex] ({x},{y}) -- ({tgt});
	\node[fill,circle,inner sep=1.5pt] at ({x},{y}) {{}};"""
	"").format(x=x, y=y, tgt=value.ptrto())

	class Array (CAni) :
	def __init__ (self, init, index=[]) :
	self.idx = {}
	if isinstance(init, int) :
	data = [None] * init
	else :
	data = list(init)
	self.data = [Value(v) for v in data]
	for name in index :
	self.index(name)
	def index (self, name, init=None) :
	self.idx[name] = self._env[name] = Value(init)
	def ptrto (self) :
	return str(id(self)).replace("-", "_")
	def __len__ (self) :
	return len(self.data)
	def __getitem__ (self, idx) :
	return self.data[idx].get()
	def __setitem__ (self, idx, val) :
	self.data[idx].set(val)
	def tex (self, w=1, h=1) :
	tpl = r"""%% array grid
	\begin{{scope}}[shift={{(-.5,-.5)}}]
	\coordinate ({id}) at (0,.5);
	\draw[very thick,opacity=0] (0,0) grid ({len},1);
	\draw (0,0) grid ({len},1);
	\end{{scope}}
	\foreach \x in {{0,...,{len_1}}} {{
	\node[below] at (\x,-.5) {{\relsize{{-2}}\color{{gray}}\texttt{{\x}}}};
	}}
	%% index
	{index}
	%% access
	{access}
	%% values
	{states}
	"""
	return cleandoc(tpl).format(len=len(self),
	len_1=len(self) - 1,
	id=self.ptrto(),
	index="\n".join(self._index()),
	access="\n".join(self._access()),
	states="\n".join(self._states()))
	def _index (self) :
	anim = Anim()
	for name, cell in self.idx.items() :
	cell.stop()
	for value, start, stop in cell.hist :
	for step in range(start, stop+1) :
	anim[step].append((name, value))
	for start, stop, info in anim.range_iter() :
	xpos = collections.defaultdict(list)
	for name, value in info :
	if value is not None :
	xpos[value].append(name)
	if not xpos :
	continue
	yield (r"\uncover<{start}-{stop}>{{"
	r"").format(start=start, stop=stop)
	for value, names in xpos.items() :
	yield (r" \node[above] at ({xpos},.5) {{\texttt{{{label}}}}};"
	r"").format(xpos=value, label=",".join(names))
	yield "}"
	def _access (self) :
	anim = Anim()
	for pos, cell in enumerate(self.data) :
	cell.stop()
	for step in cell.show :
	anim[step].append(pos)
	for steps, info in anim.steps_iter() :
	yield (r"\only<{steps}>{{"
	r"").format(steps=",".join(str(s) for s in steps))
	for pos in info :
	yield (r" \draw[very thick,blue!50!black,fill=blue!20] "
	r"({x},-.5) rectangle ++(1,1);"
	r"").format(x=pos-.5)
	yield "}"
	def _states (self) :
	anim = collections.defaultdict(list)
	for pos, cell in enumerate(self.data) :
	cell.stop()
	for value, start, stop in cell.hist :
	anim[start,stop].append((pos, value))
	def firstlargest (item) :
	return (item[0][0], -item[0][1])
	for (start, stop), info in sorted(anim.items(), key=firstlargest) :
	yield (r"\only<{start}-{stop}>{{"
	r"").format(start=start, stop=stop)
	for pos, value in info :
	yield r" \node at ({x},0) {{{val}}};".format(x=pos, val=value)
	yield "}"

	class Struct (CAni) :
	def __init__ (self, **members) :
	self.__dict__["_members"] = dict(members)
	def __getattr__ (self, name) :
	if name in self._members :
	return self._members[name].get()
	else :
	return super().__getattr__(name)
	def __setattr__ (self, name, value) :
	if name in self._members :
	self._members[name].set(value)
	else :
	super.__setattr__(name, value)
	def tex (self, w=1, h=1) :
	return "\n".join(self._tex(w, h))
	def _tex (self, w, h) :
	pos = (len(self._members) - 1) * h
	for name, cell in self._members.items() :
	yield f"%% .{name}"
	yield cell.tex(w=w, h=h, x=0, y=pos)
	yield r"\node[left] at ({pos}) {{.{name}}};".format(pos=cell.ptrto(),
	name=name)
	pos -= h

	class Data (CAni) :
	def __init__ (self, *content) :
	self.content = list(content)
	def tex (self, *args) :
	return "\n".join(self._tex(args))
	def _tex (self, args) :
	args = list(args)
	args.extend({} for i in range(len(self.content) - len(args)))
	for a, d in zip(args, self.content) :
	yield r"\begin{{scope}}[{args}]".format(args=",".join("%s=%s" % i
	for i in a.items()))
	for line in d.tex().splitlines() :
	yield " " + line
	yield r"\end{scope}"

	##
	## code blocks
	##

	class _CODE (CAni) :
	_fields = []
	_options = []
	def __init__ (self, l, *k) :
	params = []
	for i, name in enumerate(self._fields) :
	if name[0] == "*" :
	self._fields = self._fields[:]
	self._fields[i] = name[1:]
	params.append(Parameter(name[1:], Parameter.VAR_POSITIONAL))
	else :
	params.append(Parameter(name, Parameter.POSITIONAL_OR_KEYWORD))
	for name in self._options :
	params.append(Parameter(name, Parameter.POSITIONAL_OR_KEYWORD, default=None))
	params.append(Parameter("src", Parameter.KEYWORD_ONLY, default=None))
	sig = Signature(params)
	args = sig.bind(l, *k)
	args.apply_defaults()
	for key, val in args.arguments.items() :
	setattr(self, key, val)
	self._at = set()
	@property
	def last (self) :
	return self._env.get("LAST", None)
	def __str__ (self) :
	content = []
	for key, val in self.items() :
	if isinstance(val, _CODE) :
	content.append((key, str(val)))
	else :
	content.append((key, repr(val)))
	return "%s(%s)" % (self.__class__.__name__,
	", ".join("%s=%r" % item for item in content))
	def items (self) :
	for field in self._fields :
	yield field, getattr(self, field)
	for field in self._options :
	member = getattr(self, field, None)
	if member is not None :
	yield field, member
	def source (self) :
	sub = {}
	for key, val in self.items() :
	if isinstance(val, _CODE) :
	sub[key] = val.source()
	else :
	sub[key] = val
	return self.src.format(**sub)
	def tex (self) :
	sub = self.src.format(**{key : "$" for key, val in self.items()}).split("$")
	parts = [pygmentize(sub[0])]
	for (key, val), txt in zip(self.items(), sub[1:]) :
	if isinstance(val, _CODE) :
	parts.append(val.tex())
	else :
	parts.append(pygmentize(str(val)))
	parts.append(pygmentize(txt))
	tex = "".join(parts)
	if self._at :
	return r"\onlyhl{%s}{" % ",".join(str(i) for i in self._at) + tex + "}"
	else :
	return tex

	class BLOCK (_CODE) :
	_fields = ["*body"]
	def __call__ (self) :
	self._at.add(self.IP)
	for code in self.body :
	code()
	def source (self) :
	return "".join(b.source() for b in self.body)
	def tex (self) :
	return "".join(b.tex() for b in self.body)

	class STMT (_CODE) :
	_fields = ["*steps"]
	def __call__ (self) :
	for s in self.steps :
	self._at.add(self.IP)
	exec(s, self._env, self._env)
	self.IP += 1

	class EXPR (_CODE) :
	_fields = ["expr"]
	def __init__ (self, l, *k) :
	super().__init__(l, *k)
	if self.src is None :
	self.src = self.expr
	def __call__ (self) :
	self._at.add(self.IP)
	self._env["LAST"] = eval(self.expr, self._env, self._env)
	self.IP += 1

	class PY (_CODE) :
	_fields = ["py"]
	def __call__ (self) :
	exec(self.py, self._env)
	def tex (self) :
	return ""
	def source (self) :
	return ""

	class ENV (_CODE) :
	_fields = ["name", "value"]
	def __call__ (self) :
	self._env[self.name] = self.value
	def tex (self) :
	return ""
	def source (self) :
	return ""

	class WS (_CODE) :
	_fields = []
	def __init__ (self, src) :
	super().__init__(src=src)
	def __call__ (self) :
	pass
	def tex (self) :
	return self.src

	class DECL (_CODE) :
	_fields = ["name"]
	_options = ["init", "animate"]
	def __init__ (self, l, *k) :
	super().__init__(l, *k)
	if self.animate is not None :
	self._cell = self._env[self.name] = Value()
	def __call__ (self) :
	if self.init is not None :
	self.init()
	self._env[self.name] = self.last
	else :
	self._env[self.name] = None
	self._at.add(self.IP)
	self.IP += 1
	def tex (self) :
	src = super().tex()
	if self.animate is None :
	return src
	else :
	return src + " " + "".join(self._tex())
	def _tex (self) :
	tail = r"\PY{{c+c1}}{{/* {value} */}}"
	for value, start, stop in self._cell.hist :
	if value is not None :
	yield (r"\onlyshow{{{start}-{stop}}}{{{value}}}"
	r"").format(start=start or 1,
	stop=stop or "",
	value=tail.format(value=value))

	class BreakLoop (Exception) :
	def __init__ (self) :
	super().__init__()

	class BREAK (_CODE) :
	def __call__ (self) :
	self._at.add(self.IP)
	self.IP += 1
	raise BreakLoop()

	class FunctionReturn (Exception) :
	def __init__ (self, RET) :
	super().__init__()
	self.RET = RET

	class RETURN (_CODE) :
	_fields = ["value"]
	def __call__ (self) :
	self.value()
	self._at.add(self.IP)
	self.IP += 1
	raise FunctionReturn(self.last)

	class IF (_CODE) :
	_fields = ["cond", "then"]
	_options = ["otherwise"]
	def __call__ (self) :
	self.cond()
	if self.last :
	self.then()
	elif self.otherwise is not None :
	self.otherwise()

	class WHILE (_CODE) :
	_fields = ["cond", "body"]
	def __call__ (self) :
	try :
	while True :
	self.cond()
	if not self.last :
	break
	self.body()
	except BreakLoop :
	return

	class DO (_CODE) :
	_fields = ["body", "cond"]
	def __call__ (self) :
	try :
	while True :
	self.body()
	self.cond()
	if not self.last :
	break
	except BreakLoop :
	pass

	class FOR (_CODE) :
	_fields = ["init", "cond", "step", "body"]
	def __call__ (self) :
	self.init()
	try :
	while True :
	self.cond()
	if not self.last :
	break
	self.body()
	self.step()
	except BreakLoop :
	pass

	class FUNC (_CODE) :
	_fields = ["body"]
	def __call__ (self) :
	try :
	self.body()
	except FunctionReturn as exc :
	self._env["LAST"] = exc.RET
	GNU LESSER GENERAL PUBLIC LICENSE
	Version 3, 29 June 2007

	Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
	Everyone is permitted to copy and distribute verbatim copies
	of this license document, but changing it is not allowed.


	This version of the GNU Lesser General Public License incorporates
	the terms and conditions of version 3 of the GNU General Public
	License, supplemented by the additional permissions listed below.

	0. Additional Definitions.

	As used herein, "this License" refers to version 3 of the GNU Lesser
	General Public License, and the "GNU GPL" refers to version 3 of the GNU
	General Public License.

	"The Library" refers to a covered work governed by this License,
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	An "Application" is any work that makes use of an interface provided
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	and utility programs needed for reproducing the Combined Work from the
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	Library.
	from anim import *

	##
	## quicksort partitioning
	##

	array = Array([3, 13, 5, 0, 7, 11, 4, 9, 14, 2, 10, 1, 12, 8, 6],
	index=["a", "b"])
	tab = Struct(len=Value(15),
	val=Pointer(array))

	partition = FUNC(BLOCK(ENV("t", tab),
	WS(" "),
	DECL("pivot", EXPR("t.val[(t.len-1)//2]",
	src="t.val[(t.len-1)/2]"),
	animate=True,
	src="int {name} = {init};"),
	WS("\n "),
	DECL("a", EXPR("-1"),
	src="uint {name} = {init};"),
	WS("\n "),
	DECL("b", EXPR("t.len"),
	src="uint {name} = {init};"),
	WS("\n "),
	WHILE(EXPR("1", src="1"),
	BLOCK(WS(" "),
	DO(STMT("a+=1", src="a++;"),
	EXPR("t.val[a] < pivot"),
	src="do {{ {body} }} while ({cond});"),
	WS("\n "),
	DO(STMT("b-=1", src="b--;"),
	EXPR("t.val[b] > pivot"),
	src="do {{ {body} }} while ({cond});"),
	WS("\n "),
	IF(EXPR("a >= b"),
	RETURN(EXPR("b"),
	src="return {value};"),
	src="if ({cond}) {{ {then} }}"),
	WS("\n "),
	STMT("_old = t.val[a], t.val[b]",
	"t.val[b], t.val[a] = _old",
	src="swap(t, a, b);"),
	WS("\n")),
	src="while ({cond}) {{\n{body} }}"),
	WS("\n")),
	src="uint partition (Tab t) {{\n{body}}}\n")

	# run code and save its animation
	partition.IP += 1
	partition()
	with open("code.tex", "w") as out :
	out.write(partition.tex())

	# save data anaimation
	data = Data(array, tab)
	with open("code.tikz", "w") as out :
	out.write(data.tex({"shift": "{(2.5,0)}"}, {}))
	\documentclass{beamer}

	\usepackage[francais]{babel}
	\usepackage[utf8x]{inputenc}
	\usepackage[T1]{fontenc}
	\usepackage{ae}
	\usepackage{tikz}
	\usepackage{adjustbox}
	\usepackage{fancyvrb}
	\usepackage{pygments}
	\usepackage{relsize}

	\usetikzlibrary{arrows}

	\def\hl #1{{\setbox0=\hbox{#1}%
	\adjustbox{set vsize={\ht0}{\dp0}}{\hbox to \wd0{\hss\colorbox{yellow}{#1}\hss}}}}

	\def\hl #1{%
	\tikz[overlay,baseline,inner sep=1pt]
	\node[fill=yellow,anchor=text] {\color{yellow}#1};%
	#1%
	}%

	\def\onlyhl #1{\only<#1>\hl}
	\def\onlyshow #1{\only<#1>}

	\begin{document}

	\begin{frame}[fragile]{Tri rapide: algorithme de partitionnement}
	\VerbatimInput[commandchars=\\\{\}]{code.tex}
	\begin{tikzpicture}[scale=.55]
	\input{code.tikz}
	\end{tikzpicture}
	\end{frame}

	\end{document}