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|
% \iffalse meta-comment
%
% Copyright 2009, 2010 by Élie Roux <elie.roux@telecom-bretagne.eu>
% Copyright 2010, 2011 by Manuel Pégourié-Gonnard <mpg@elzevir.fr>
% Copyright 2013 by Philipp Gesang <philipp.gesang@alumni.uni-heidelberg.de>
%
% This work is under the CC0 license.
%
% This work consists of the main source file luatexbase-mcb.dtx
% and the derived files
% luatexbase-mcb.sty, mcb.lua, luatexbase-mcb.pdf,
% test-mcb-plain.tex test-mcb-latex.tex
%
% Unpacking:
% tex luatexbase-mcb.dtx
% Documentation:
% pdflatex luatexbase-mcb.dtx
%
%<*ignore>
\begingroup
\def\x{LaTeX2e}%
\expandafter\endgroup
\ifcase 0\ifx\install y1\fi\expandafter
\ifx\csname processbatchFile\endcsname\relax\else1\fi
\ifx\fmtname\x\else 1\fi\relax
\else\csname fi\endcsname
%</ignore>
%<*install>
\input docstrip.tex
\keepsilent
\askforoverwritefalse
\let\MetaPrefix\relax
\preamble
See the aforementioned source file(s) for copyright and licensing information.
\endpreamble
\let\MetaPrefix\DoubleperCent
\generate{%
\usedir{tex/luatex/luatexbase}%
\file{luatexbase-mcb.sty}{\from{luatexbase-mcb.dtx}{texpackage}}%
}
\generate{%
\usedir{doc/luatex/luatexbase}%
\file{test-mcb-plain.tex}{\from{luatexbase-mcb.dtx}{testplain}}%
\file{test-mcb-latex.tex}{\from{luatexbase-mcb.dtx}{testlatex}}%
}
\def\MetaPrefix{-- }
\def\luapostamble{%
\MetaPrefix^^J%
\MetaPrefix\space End of File `\outFileName'.%
}
\def\currentpostamble{\luapostamble}%
\generate{%
\usedir{tex/luatex/luatexbase}%
\file{mcb.lua}{\from{luatexbase-mcb.dtx}{lua}}%
}
\generate{%
\usedir{doc/luatex/luatexbase}%
\file{test-mcb.lua}{\from{luatexbase-mcb.dtx}{testlua}}%
}
\obeyspaces
\Msg{************************************************************************}
\Msg{*}
\Msg{* To finish the installation you have to move the following}
\Msg{* files into a directory searched by TeX:}
\Msg{*}
\Msg{* luatexbase-mcb.sty mcb.lua}
\Msg{*}
\Msg{* Happy TeXing!}
\Msg{*}
\Msg{************************************************************************}
\endbatchfile
%</install>
%<*ignore>
\fi
%</ignore>
%<*driver>
\documentclass{ltxdoc}
\input{lltxb-dtxstyle}
\begin{document}
\DocInput{luatexbase-mcb.dtx}%
\end{document}
%</driver>
% \fi
%
% \CheckSum{0}
%
% \CharacterTable
% {Upper-case \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z
% Lower-case \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z
% Digits \0\1\2\3\4\5\6\7\8\9
% Exclamation \! Double quote \" Hash (number) \#
% Dollar \$ Percent \% Ampersand \&
% Acute accent \' Left paren \( Right paren \)
% Asterisk \* Plus \+ Comma \,
% Minus \- Point \. Solidus \/
% Colon \: Semicolon \; Less than \<
% Equals \= Greater than \> Question mark \?
% Commercial at \@ Left bracket \[ Backslash \\
% Right bracket \] Circumflex \^ Underscore \_
% Grave accent \` Left brace \{ Vertical bar \|
% Right brace \} Tilde \~}
%
% \pkdate{luatexbase-mcb}{2013/04/13 v0.5}
%
% \maketitle
%
% \begin{abstract}
% The primary feature of this package is to allow many functions to be
% registered in the same callback. Depending of the type of the callback, the
% functions will be combined in some way when the callback is called. Functions
% are provided for addition and removal of individual functions from a
% callback's list, with a priority system.\par
% Additionally, you can create new callbacks that will be handled the same way
% as predefined callbacks, except that they must be called explicitly.
% \end{abstract}
%
% \tableofcontents
%
% \section{Documentation}
%
% Before we start, let me mention that test files are provided (they should be
% in the same directory as this PDF file). You can have a look at them,
% compile them and have a look at the log, if you want examples of how this
% module works.
%
% \subsection{Managing functions in callbacks}
%
% \luatex provides an extremely interesting feature, named callbacks. It
% allows to call some Lua functions at some points of the \TeX\ algorithm (a
% \emph{callback}), like when \TeX\ breaks lines, puts vertical spaces, etc.
% The \luatex core offers a function called \texttt{callback.register} that
% enables to register a function in a callback.
%
% The problem with |callback.register| is that is registers only one function
% in a callback. This package solves the problem by disabling
% |callback.register| and providing a new interface allowing many functions to
% be registered in a single callback.
%
% The way the functions are combined together depends on
% the type of the callback. There are currently 4 types of callback, depending
% on the calling convention of the functions the callback can hold:
% \begin{description}
% \item[simple] is for functions that don't return anything: they are called
% in order, all with the same argument;
% \item[data] is for functions receiving a piece of data of any type
% except node list head (and possibly other arguments) and returning it
% (possibly modified): the functions are called in order, and each is
% passed the return value of the previous (and the other arguments
% untouched, if any). The return value is that of the last function;
% \item[list] is a specialized variant of \emph{data} for functions
% filtering node lists. Such functions may return either the head of a
% modified node list, or the boolean values |true| or |false|. The
% functions are chained the same way as for \emph{data} except that for
% the following. If
% one function returns |false|, then |false| is immediately returned and
% the following functions are \emph{not} called. If one function returns
% |true|, then the same head is passed to the next function. If all
% functions return |true|, then |true| is returned, otherwise the return
% value of the last function not returning |true| is used.
% \item[first] is for functions with more complex signatures; functions in
% this type of callback are \emph{not} combined: only the first one
% (according to priorities) is executed.
% \end{description}
%
% To add a function to a callback, use:
% \begin{verbatim}
% luatexbase.add_to_callback(name, func, description, priority)
% \end{verbatim}
% The first argument is the name of the callback, the second is a function,
% the third one is a string used to identify the function later, and the
% optional priority is a positive integer, representing the rank of the
% function in the list of functions to be executing for this callback. So,
% |1| is the highest priority. If no priority is specified, the function is
% appended to the list, that is, its priority is the one of the last function
% plus one.
%
% The priority system is intended to help resolving conflicts between packages
% competing on the same callback, but it cannot solve every possible issue. If
% two packages request priority |1| on the same callback, then the last one
% loaded will win.
%
% To remove a function from a callback, use:
% \begin{verbatim}
% luatexbase.remove_from_callback(name, description)
% \end{verbatim}
% The first argument must be the name of the callback, and the second one the
% description used when adding the function to this callback. You can also
% remove all functions from a callback at once using
% \begin{verbatim}
% luatexbase.reset_callback(name, make_false)
% \end{verbatim}
% The |make_false| argument is optional. If it is |true| (repeat: |true|, not
% |false|) then the value |false| is registered in the callback, which has a
% special meaning for some callback.
%
% Note that |reset_callback| is very invasive since it removes all functions
% possibly installed by other packages in this callback. So, use it with care
% if there is any chance that another package wants to share this callback
% with you.
%
% When new functions are added at the beginning of the list, other functions
% are shifted down the list. To get the current rank of a function in a
% callback's list, use:
% \begin{verbatim}
% priority = luatexbase.priority_in_callback(name, description)
% \end{verbatim}
% Again, the description is the string used when adding the function. If the
% function identified by this string is not in this callback's list, the
% priority returned is the boolean value |false|.
%
% \subsection{Creating new callbacks}
%
% This package also provides a way to create and call new callbacks, in
% addition to the default \luatex callbacks.
% \begin{verbatim}
% luatexbase.create_callback(name, type, default)
% \end{verbatim}
% The first argument is the callback's name, it must be unique. Then, the type
% goes as explained above, it is given as a string. Finally all user-defined
% callbacks have a default function which must\footnote{You can obviously
% provide a dummy function. If you're doing so often, please tell me, I may
% want to make this argument optional.} be provided as the third
% argument. It will be used when no other function is registered for this
% callback.
%
% Functions are added to and removed from user-defined callbacks just the same
% way as predefined callback, so the previous section still applies. There is
% one difference, however: user-defined callbacks must be called explicitly at
% some point in your code, while predefined callbacks are called automatically
% by \luatex. To do so, use:
% \begin{verbatim}
% luatexbase.call_callback(name, arguments...)
% \end{verbatim}
% The functions registered for this callback (or the default function) will be
% called with |arguments...| as arguments.
%
% \subsubsection{Limitations}
%
% For callbacks of type |first|, our new management system isn't actually
% better than good old |callback.register|. For some of them, is may be
% possible to split them into many callbacks, so that these callbacks can
% accept multiple functions. However, its seems risky and limited in use and
% is therefore nor implemented.
%
% At some point, \pk{luatextra} used to split |open_read_file| that way, but
% support for this was removed. It may be added back (as well as support for
% other split callbacks) if it appears there is an actual need for it.
%
% \subsection{Compatibility}
%
% Some callbacks have a calling convention that varies depending on the
% version of \luatex used. This package \emph{does not} try to track the type
% of the callbacks in every possible version of \luatex. The types are based
% on the last stable beta version (0.60.2 at the time this doc is written).
%
% However, for callbacks that have the same calling convention for every
% version of \luatex, this package should work with the same range of \luatex
% version as other packages in the \pk{luatexbase} bundle (currently, 0.25.4
% to 0.60.2).
%
% \section{Implementation}
%
% \subsection{\tex package}
%
% \begin{macrocode}
%<*texpackage>
% \end{macrocode}
%
% \subsubsection{Preliminaries}
%
% Catcode defenses and reload protection.
%
% \begin{macrocode}
\begingroup\catcode61\catcode48\catcode32=10\relax% = and space
\catcode123 1 % {
\catcode125 2 % }
\catcode 35 6 % #
\toks0\expandafter{\expandafter\endlinechar\the\endlinechar}%
\edef\x{\endlinechar13}%
\def\y#1 #2 {%
\toks0\expandafter{\the\toks0 \catcode#1 \the\catcode#1}%
\edef\x{\x \catcode#1 #2}}%
\y 13 5 % carriage return
\y 61 12 % =
\y 32 10 % space
\y 123 1 % {
\y 125 2 % }
\y 35 6 % #
\y 64 11 % @ (letter)
\y 10 12 % new line ^^J
\y 39 12 % '
\y 40 12 % (
\y 41 12 % )
\y 45 12 % -
\y 46 12 % .
\y 47 12 % /
\y 58 12 % :
\y 91 12 % [
\y 93 12 % ]
\y 94 7 % ^
\y 96 12 % `
\toks0\expandafter{\the\toks0 \relax\noexpand\endinput}%
\edef\y#1{\noexpand\expandafter\endgroup%
\noexpand\ifx#1\relax \edef#1{\the\toks0}\x\relax%
\noexpand\else \noexpand\expandafter\noexpand\endinput%
\noexpand\fi}%
\expandafter\y\csname luatexbase@mcb@sty@endinput\endcsname%
% \end{macrocode}
%
% Package declaration.
%
% \begin{macrocode}
\begingroup
\expandafter\ifx\csname ProvidesPackage\endcsname\relax
\def\x#1[#2]{\immediate\write16{Package: #1 #2}}
\else
\let\x\ProvidesPackage
\fi
\expandafter\endgroup
\x{luatexbase-mcb}[2013/04/13 v0.5 Callback management for LuaTeX]
% \end{macrocode}
%
% Make sure \luatex is used.
%
% \begin{macrocode}
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname RequirePackage\endcsname\relax
\input ifluatex.sty
\else
\RequirePackage{ifluatex}
\fi
\ifluatex\else
\begingroup
\expandafter\ifx\csname PackageError\endcsname\relax
\def\x#1#2#3{\begingroup \newlinechar10
\errhelp{#3}\errmessage{Package #1 error: #2}\endgroup}
\else
\let\x\PackageError
\fi
\expandafter\endgroup
\x{luatexbase-mcb}{LuaTeX is required for this package. Aborting.}{%
This package can only be used with the LuaTeX engine^^J%
(command `lualatex' or `luatex').^^J%
Package loading has been stopped to prevent additional errors.}
\expandafter\luatexbase@mcb@sty@endinput%
\fi
% \end{macrocode}
%
% \subsubsection{Load supporting Lua module}
%
% First load \pk{luatexbase-loader} (hence \pk{luatexbase-compat}), then
% the supporting Lua module.
%
% \begin{macrocode}
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname RequirePackage\endcsname\relax
\input luatexbase-modutils.sty
\else
\RequirePackage{luatexbase-modutils}
\fi
\luatexbase@directlua{require('luatexbase.mcb')}
% \end{macrocode}
%
% That's all folks!
%
% \begin{macrocode}
\luatexbase@mcb@sty@endinput%
%</texpackage>
% \end{macrocode}
%
% \subsection{Lua module}
%
% \begin{macrocode}
%<*lua>
% \end{macrocode}
%
% \subsubsection{Module identification}
%
% \begin{macrocode}
luatexbase = luatexbase or { }
local luatexbase = luatexbase
local err, warning, info, log = luatexbase.provides_module({
name = "luatexbase-mcb",
version = 0.5,
date = "2013/04/13",
description = "register several functions in a callback",
author = "Hans Hagen, Elie Roux, Manuel Pegourie-Gonnard and Philipp Gesang",
copyright = "Hans Hagen, Elie Roux, Manuel Pegourie-Gonnard and Philipp Gesang",
license = "CC0",
})
% \end{macrocode}
%
% First we declare the function references for the entire scope.
%
% \begin{macrocode}
local add_to_callback
local call_callback
local create_callback
local priority_in_callback
local remove_from_callback
local reset_callback
% \end{macrocode}
%
% \subsubsection{Housekeeping}
%
% The main table: keys are callback names, and values are the associated
% lists of functions. More precisely, the entries in the list are tables
% holding the actual function as |func| and the identifying description as
% |description|. Only callbacks with a non-empty list of functions have an
% entry in this list.
%
% \begin{macrocode}
local callbacklist = callbacklist or { }
% \end{macrocode}
%
% Numerical codes for callback types, and name to value association (the
% table keys are strings, the values are numbers).
%
% \begin{macrocode}
local list, data, first, simple = 1, 2, 3, 4
local types = {
list = list,
data = data,
first = first,
simple = simple,
}
% \end{macrocode}
%
% Now, list all predefined callbacks with their current type, based on the
% LuaTeX manual version 0.60.2.
%
% \begin{macrocode}
local callbacktypes = callbacktypes or {
% \end{macrocode}
%
% Section 4.1.1: file discovery callbacks.
%
% \begin{macrocode}
find_read_file = first,
find_write_file = first,
find_font_file = data,
find_output_file = data,
find_format_file = data,
find_vf_file = data,
find_ocp_file = data,
find_map_file = data,
find_enc_file = data,
find_sfd_file = data,
find_pk_file = data,
find_data_file = data,
find_opentype_file = data,
find_truetype_file = data,
find_type1_file = data,
find_image_file = data,
% \end{macrocode}
%
% Section 4.1.2: file reading callbacks.
%
% \begin{macrocode}
open_read_file = first,
read_font_file = first,
read_vf_file = first,
read_ocp_file = first,
read_map_file = first,
read_enc_file = first,
read_sfd_file = first,
read_pk_file = first,
read_data_file = first,
read_truetype_file = first,
read_type1_file = first,
read_opentype_file = first,
% \end{macrocode}
%
% Section 4.1.3: data processing callbacks.
%
% \begin{macrocode}
process_input_buffer = data,
process_output_buffer = data,
token_filter = first,
% \end{macrocode}
%
% Section 4.1.4: node list processiong callbacks.
%
% \begin{macrocode}
buildpage_filter = simple,
pre_linebreak_filter = list,
linebreak_filter = list,
post_linebreak_filter = list,
hpack_filter = list,
vpack_filter = list,
pre_output_filter = list,
hyphenate = simple,
ligaturing = simple,
kerning = simple,
mlist_to_hlist = list,
% \end{macrocode}
%
% Section 4.1.5: information reporting callbacks.
%
% \begin{macrocode}
start_run = simple,
stop_run = simple,
start_page_number = simple,
stop_page_number = simple,
show_error_hook = simple,
% \end{macrocode}
%
% Section 4.1.6: font-related callbacks.
%
% \begin{macrocode}
define_font = first,
}
% \end{macrocode}
%
% All user-defined callbacks have a default function. The following table's
% keys are the names of the user-defined callback, the associated value is
% the default functon for this callback. This table is also used to
% identify the user-defined callbacks.
%
% \begin{macrocode}
local lua_callbacks_defaults = { }
% \end{macrocode}
%
% Overwrite |callback.register|, but save it first. Also define a wrapper
% that automatically raise an error when something goes wrong.
%
% \begin{macrocode}
local original_register = original_register or callback.register
callback.register = function ()
err("function callback.register has been trapped,\n"
.."please use luatexbase.add_to_callback instead.")
end
local function register_callback(...)
return assert(original_register(...))
end
% \end{macrocode}
%
% \subsubsection{Handlers}
%
% Normal (as opposed to user-defined) callbacks have handlers depending on
% their type. The handler function is registered into the callback when the
% first function is added to this callback's list. Then, when the callback
% is called, then handler takes care of running all functions in the list.
% When the last function is removed from the callback's list, the handler
% is unregistered.
%
% More precisely, the functions below are used to generate a specialized
% function (closure) for a given callback, which is the actual handler.
%
% Handler for |list| callbacks.
%
% \begin{macrocode}
local function listhandler (name)
return function(head,...)
local ret
local alltrue = true
for _, f in ipairs(callbacklist[name]) do
ret = f.func(head, ...)
if ret == false then
warning("function '%s' returned false\nin callback '%s'",
f.description, name)
break
end
if ret ~= true then
alltrue = false
head = ret
end
end
return alltrue and true or head
end
end
% \end{macrocode}
%
% Handler for |data| callbacks.
%
% \begin{macrocode}
local function datahandler (name)
return function(data, ...)
for _, f in ipairs(callbacklist[name]) do
data = f.func(data, ...)
end
return data
end
end
% \end{macrocode}
%
% Handler for |first| callbacks. We can assume |callbacklist[name]| is not
% empty: otherwise, the function wouldn't be registered in the callback any
% more.
%
% \begin{macrocode}
local function firsthandler (name)
return function(...)
return callbacklist[name][1].func(...)
end
end
% \end{macrocode}
%
% Handler for |simple| callbacks.
%
% \begin{macrocode}
local function simplehandler (name)
return function(...)
for _, f in ipairs(callbacklist[name]) do
f.func(...)
end
end
end
% \end{macrocode}
%
% Finally, keep a handlers table for indexed access.
%
% \begin{macrocode}
local handlers = {
[list] = listhandler,
[data] = datahandler,
[first] = firsthandler,
[simple] = simplehandler,
}
% \end{macrocode}
%
% \subsubsection{Public functions for functions management}
%
% Add a function to a callback. First check arguments.
%
% \begin{macrocode}
function add_to_callback (name,func,description,priority)
if type(func) ~= "function" then
return err("unable to add function:\nno proper function passed")
end
if not name or name == "" then
err("unable to add function:\nno proper callback name passed")
return
elseif not callbacktypes[name] then
err("unable to add function:\n'%s' is not a valid callback", name)
return
end
if not description or description == "" then
err("unable to add function to '%s':\nno proper description passed",
name)
return
end
if priority_in_callback(name, description) then
err("function '%s' already registered\nin callback '%s'",
description, name)
return
end
% \end{macrocode}
%
% Then test if this callback is already in use. If not, initialise its list
% and register the proper handler.
%
% \begin{macrocode}
local l = callbacklist[name]
if not l then
l = {}
callbacklist[name] = l
if not lua_callbacks_defaults[name] then
register_callback(name, handlers[callbacktypes[name]](name))
end
end
% \end{macrocode}
%
% Actually register the function.
%
% \begin{macrocode}
local f = {
func = func,
description = description,
}
priority = tonumber(priority)
if not priority or priority > #l then
priority = #l+1
elseif priority < 1 then
priority = 1
end
table.insert(l,priority,f)
% \end{macrocode}
%
% Keep user informed.
%
% \begin{macrocode}
if callbacktypes[name] == first and #l ~= 1 then
warning("several functions in '%s',\n"
.."only one will be active.", name)
end
log("inserting '%s'\nat position %s in '%s'",
description, priority, name)
end
luatexbase.add_to_callback = add_to_callback
% \end{macrocode}
%
% Remove a function from a callback. First check arguments.
%
% \begin{macrocode}
function remove_from_callback (name, description)
if not name or name == "" then
err("unable to remove function:\nno proper callback name passed")
return
elseif not callbacktypes[name] then
err("unable to remove function:\n'%s' is not a valid callback", name)
return
end
if not description or description == "" then
err(
"unable to remove function from '%s':\nno proper description passed",
name)
return
end
local l = callbacklist[name]
if not l then
err("no callback list for '%s'",name)
return
end
% \end{macrocode}
%
% Then loop over the callback's function list until we find a matching
% entry. Remove it and check if the list gets empty: if so, unregister the
% callback handler unless the callback is user-defined.
%
% \begin{macrocode}
local index = false
for k,v in ipairs(l) do
if v.description == description then
index = k
break
end
end
if not index then
err("unable to remove '%s'\nfrom '%s'", description, name)
return
end
table.remove(l, index)
log("removing '%s'\nfrom '%s'", description, name)
if #l == 0 then
callbacklist[name] = nil
if not lua_callbacks_defaults[name] then
register_callback(name, nil)
end
end
return
end
luatexbase.remove_from_callback = remove_from_callback
% \end{macrocode}
%
% Remove all the functions registered in a callback. Unregisters the
% callback handler unless the callback is user-defined.
%
% \begin{macrocode}
function reset_callback (name, make_false)
if not name or name == "" then
err("unable to reset:\nno proper callback name passed")
return
elseif not callbacktypes[name] then
err("unable to reset '%s':\nis not a valid callback", name)
return
end
log("resetting callback '%s'", name)
callbacklist[name] = nil
if not lua_callbacks_defaults[name] then
if make_false == true then
log("setting '%s' to false", name)
register_callback(name, false)
else
register_callback(name, nil)
end
end
end
luatexbase.reset_callback = reset_callback
% \end{macrocode}
%
% Get a function's priority in a callback list, or false if the function is
% not in the list.
%
% \begin{macrocode}
function priority_in_callback (name, description)
if not name or name == ""
or not callbacktypes[name]
or not description then
return false
end
local l = callbacklist[name]
if not l then return false end
for p, f in pairs(l) do
if f.description == description then
return p
end
end
return false
end
luatexbase.priority_in_callback = priority_in_callback
% \end{macrocode}
%
% \subsubsection{Public functions for user-defined callbacks}
%
% This first function creates a new callback. The signature is
% \texttt{create(name, ctype, default)} where \texttt{name} is the name of
% the new callback to create, \texttt{ctype} is the type of callback, and
% \texttt{default} is the default function to call if no function is
% registered in this callback.
%
% The created callback will behave the same way Lua\TeX\ callbacks do, you
% can add and remove functions in it. The difference is that the callback
% is not automatically called, the package developer creating a new
% callback must also call it, see next function.
%
% \begin{macrocode}
function create_callback(name, ctype, default)
if not name then
err("unable to call callback:\nno proper name passed", name)
return nil
end
if not ctype or not default then
err("unable to create callback '%s':\n"
.."callbacktype or default function not specified", name)
return nil
end
if callbacktypes[name] then
err("unable to create callback '%s':\ncallback already exists", name)
return nil
end
ctype = types[ctype]
if not ctype then
err("unable to create callback '%s':\ntype '%s' undefined", name, ctype)
return nil
end
log("creating '%s' type %s", name, ctype)
lua_callbacks_defaults[name] = default
callbacktypes[name] = ctype
end
luatexbase.create_callback = create_callback
% \end{macrocode}
%
% This function calls a callback. It can only call a callback created by
% the \texttt{create} function.
%
% \begin{macrocode}
function call_callback(name, ...)
if not name then
err("unable to call callback:\nno proper name passed", name)
return nil
end
if not lua_callbacks_defaults[name] then
err("unable to call lua callback '%s':\nunknown callback", name)
return nil
end
local l = callbacklist[name]
local f
if not l then
f = lua_callbacks_defaults[name]
else
f = handlers[callbacktypes[name]](name)
if not f then
err("unknown callback type")
return
end
end
return f(...)
end
luatexbase.call_callback = call_callback
% \end{macrocode}
%
% That's all folks!
%
% \begin{macrocode}
%</lua>
% \end{macrocode}
%
% \section{Test files}
%
% A few basic tests for Plain and LaTeX. Use a separate Lua file for
% convenience, since this package works on the Lua side of the force.
%
% \begin{macrocode}
%<*testlua>
local msg = texio.write_nl
% \end{macrocode}
%
% Test the management functions with a predefined callback.
%
% \begin{macrocode}
local function sample(head,...)
return head, true
end
local prio = luatexbase.priority_in_callback
msg("\n*********\n* Testing management functions\n*********")
luatexbase.add_to_callback("hpack_filter", sample, "sample one", 1)
luatexbase.add_to_callback("hpack_filter", sample, "sample two", 2)
luatexbase.add_to_callback("hpack_filter", sample, "sample three", 1)
assert(prio("hpack_filter", "sample three"))
luatexbase.remove_from_callback("hpack_filter", "sample three")
assert(not prio("hpack_filter", "sample three"))
luatexbase.reset_callback("hpack_filter")
assert(not prio("hpack_filter", "sample one"))
% \end{macrocode}
%
% Create a callback, and check that the managment functions work with this
% callback too.
%
% \begin{macrocode}
local function data_one(s)
texio.write_nl("I'm data 1 whith argument: "..s)
return s
end
local function data_two(s)
texio.write_nl("I'm data 2 whith argument: "..s)
return s
end
local function data_three(s)
texio.write_nl("I'm data 3 whith argument: "..s)
return s
end
msg("\n*********\n* Testing user-defined callbacks\n*********")
msg("* create one")
luatexbase.create_callback("fooback", "data", data_one)
msg("* call it")
luatexbase.call_callback("fooback", "default")
msg("* add two functions")
luatexbase.add_to_callback("fooback", data_two, "function two", 2)
luatexbase.add_to_callback("fooback", data_three, "function three", 1)
msg("* call")
luatexbase.call_callback("fooback", "all")
msg("* rm one function")
luatexbase.remove_from_callback("fooback", "function three")
msg("* call")
luatexbase.call_callback("fooback", "all but three")
msg("* reset")
luatexbase.reset_callback("fooback")
msg("* call")
luatexbase.call_callback("fooback", "default")
% \end{macrocode}
%
% Now, we want to make each handler run at least once. So, define dummy
% functions and register them in various callbacks. We will make sure the
% callbacks are executed on the \tex end. Also, we want to check that
% everything works when we unload the functions either one by one, or using
% reset.
%
% A |list| callback.
%
% \begin{macrocode}
function add_hpack_filter()
luatexbase.add_to_callback('hpack_filter', function(head, ...)
texio.write_nl("I'm a dummy hpack_filter")
return head
end,
'dummy hpack filter')
luatexbase.add_to_callback('hpack_filter', function(head, ...)
texio.write_nl("I'm an optimized dummy hpack_filter")
return true
end,
'optimized dummy hpack filter')
end
function rm_one_hpack_filter()
luatexbase.remove_from_callback('hpack_filter', 'dummy hpack filter')
end
function rm_two_hpack_filter()
luatexbase.remove_from_callback('hpack_filter',
'optimized dummy hpack filter')
end
% \end{macrocode}
%
% A |simple| callback.
%
% \begin{macrocode}
function add_hyphenate()
luatexbase.add_to_callback('hyphenate', function(head, tail)
texio.write_nl("I'm a dummy hyphenate")
end,
'dummy hyphenate')
luatexbase.add_to_callback('hyphenate', function(head, tail)
texio.write_nl("I'm an other dummy hyphenate")
end,
'other dummy hyphenate')
end
function rm_one_hyphenate()
luatexbase.remove_from_callback('hyphenate', 'dummy hyphenate')
end
function rm_two_hyphenate()
luatexbase.remove_from_callback('hyphenate', 'other dummy hyphenate')
end
% \end{macrocode}
%
% A |first| callback.
%
% \begin{macrocode}
function add_find_write_file()
luatexbase.add_to_callback('find_write_file', function(id, name)
texio.write_nl("I'm a dummy find_write_file")
return "dummy-"..name
end,
'dummy find_write_file')
luatexbase.add_to_callback('find_write_file', function(id, name)
texio.write_nl("I'm an other dummy find_write_file")
return "dummy-other-"..name
end,
'other dummy find_write_file')
end
function rm_one_find_write_file()
luatexbase.remove_from_callback('find_write_file',
'dummy find_write_file')
end
function rm_two_find_write_file()
luatexbase.remove_from_callback('find_write_file',
'other dummy find_write_file')
end
% \end{macrocode}
%
% A |data| callback.
%
% \begin{macrocode}
function add_process_input_buffer()
luatexbase.add_to_callback('process_input_buffer', function(buffer)
return buffer.."\\msg{dummy}"
end,
'dummy process_input_buffer')
luatexbase.add_to_callback('process_input_buffer', function(buffer)
return buffer.."\\msg{otherdummy}"
end,
'other dummy process_input_buffer')
end
function rm_one_process_input_buffer()
luatexbase.remove_from_callback('process_input_buffer',
'dummy process_input_buffer')
end
function rm_two_process_input_buffer()
luatexbase.remove_from_callback('process_input_buffer',
'other dummy process_input_buffer')
end
% \end{macrocode}
%
% \begin{macrocode}
%</testlua>
% \end{macrocode}
%
% \begin{macrocode}
%<testplain>\input luatexbase-mcb.sty
%<testlatex>\RequirePackage{luatexbase-mcb}
%<*testplain,testlatex>
\catcode 64 11
\def\msg{\immediate\write16}
\msg{===== BEGIN =====}
% \end{macrocode}
%
% Loading the lua files tests that the management functions can be called
% without raising errors.
%
% \begin{macrocode}
\luatexbase@directlua{dofile('test-mcb.lua')}
% \end{macrocode}
%
% We now want to load and unload stuff from the various callbacks have them
% called to test the handlers. Here is a helper macro for that.
%
% \begin{macrocode}
\def\test#1#2{%
\msg{^^J*********^^J* Testing #1 (type #2)^^J*********}
\msg{* Add two functions}
\luatexbase@directlua{add_#1()}
\csname test_#1\endcsname
\msg{* Remove one}
\luatexbase@directlua{rm_one_#1()}
\csname test_#1\endcsname
\msg{* Remove the second}
\luatexbase@directlua{rm_two_#1()}
\csname test_#1\endcsname
\msg{* Add two functions again}
\luatexbase@directlua{add_#1()}
\csname test_#1\endcsname
\msg{* Remove all functions}
\luatexbase@directlua{luatexbase.reset_callback("#1")}
\csname test_#1\endcsname
}
% \end{macrocode}
%
% For each callback, we need a specific macro that triggers it. For the
% hyphenate test, we need to untrap |\everypar| first, in the \latex case.
%
% \begin{macrocode}
\catcode`\_ 11
%<testlatex>\everypar{}
\def\test_hpack_filter{\setbox0=\hbox{bla}}
\def\test_hyphenate{\showhyphens{hyphenation}}
\def\test_find_write_file{\immediate\openout15 test-mcb-out.log}
\def\test_process_input_buffer{\input test-mcb-aux.tex}
% \end{macrocode}
%
% Now actually test them
%
% \begin{macrocode}
\test{hpack_filter}{list}
\test{hyphenate}{simple}
\test{find_write_file}{first}
\test{process_input_buffer}{data}
% \end{macrocode}
%
% Done.
%
% \begin{macrocode}
\msg{===== END =====}
%</testplain,testlatex>
%<testplain>\bye
%<testlatex>\stop
% \end{macrocode}
%
% \Finale
\endinput
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