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Diffstat (limited to 'Master/texmf-dist/source/luatex/luatexbase/luatexbase-mcb.dtx')
-rw-r--r-- | Master/texmf-dist/source/luatex/luatexbase/luatexbase-mcb.dtx | 984 |
1 files changed, 628 insertions, 356 deletions
diff --git a/Master/texmf-dist/source/luatex/luatexbase/luatexbase-mcb.dtx b/Master/texmf-dist/source/luatex/luatexbase/luatexbase-mcb.dtx index 09c8c1c53dd..b944cd261e4 100644 --- a/Master/texmf-dist/source/luatex/luatexbase/luatexbase-mcb.dtx +++ b/Master/texmf-dist/source/luatex/luatexbase/luatexbase-mcb.dtx @@ -69,6 +69,11 @@ See source file '\inFileName' for details. \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{*} @@ -113,73 +118,163 @@ See source file '\inFileName' for details. % Grave accent \` Left brace \{ Vertical bar \| % Right brace \} Tilde \~} % -% \title{The \textsf{luatexbase-mcb} package} -% \date{2010/05/27 v0.2a} -% \author{% -% Manuel P\'egouri\'e-Gonnard \\ \email{mpg@elzevir.fr} \and -% \'Elie Roux \\ \email{elie.roux@telecom-bretagne.eu}} +% \pkdate{luatexbase-mcb}{2010/10/10 v0.3} % % \maketitle % % \begin{abstract} -% This package manages the callback adding and removing, by providing new -% functions and overwriting \texttt{callback.register}. It also allows to -% create and call new callbacks.\par -% The user part of this documentation is currently very incomplete, and will -% be expanded later. Sorry for this and thanks for your patience.\par -% \textbf{Warning.} Currently assumes that \textsf{luatexbase-modutils} -% has been previously loaded. (This is a temporary limitation.) +% 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} % -% Lua\TeX\ provides an extremely interesting feature, named callbacks. It -% allows to call some lua functions at some points of the \TeX\ algorithm (a +% 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 likes, puts vertical spaces, etc. -% The Lua\TeX\ core offers a function called \texttt{callback.register} that +% The \luatex core offers a function called \texttt{callback.register} that % enables to register a function in a callback. % -% The problem with \texttt{callback.register} is that is registers only one -% function in a callback. For a lot of callbacks it can be common to have -% several packages registering their function in a callback, and thus it is -% impossible with them to be compatible with each other. -% -% This package solves this problem by adding mainly one new function -% \verb+luatexbase.add_to_callback+ that adds a function in a callback. With -% this function it is possible for packages to register their function in a -% callback without overwriting the functions of the other packages. There are -% also functions to remove one or all functions from a callback. -% See comments in the implementation section for details. -% -% The functions are called in a certain order, and when a package registers a -% callback it can assign a priority to its function. Conflicts can still -% remain even with the priority mechanism, for example in the case where two -% packages want to have the highest priority. In these cases the packages have -% to solve the conflicts themselves. -% See comments in the implementation section for details. -% -% This package also privides a way to create and call new callbacks, in -% addition to the default Lua\TeX\ callbacks. -% See comments in the implementation section for details. -% -% \subsubsection*{Limitations} -% -% This package only works for callbacks where it's safe to add multiple -% functions without changing the functions' signatures. There are callbacks, -% though, where registering several functions is not possible without changing -% the function's signatures, like for example the readers callbacks. These -% callbacks take a filename and give the datas in it. One solution would be to -% change the functions' signature to open it when the function is the first, -% and to take the datas and modify them eventually if they are called after -% the first. But it seems rather fragile and useless, so it's not implemented. -% With these callbacks, in this package we simply execute the first function -% in the list. -% -% Other callbacks in this case are \texttt{define\_font} and -% \texttt{open\_read\_file}. There is though a solution for several packages -% to use these callbacks, see the implementation of \texttt{luatextra}. +% 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 nay 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 return 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} % @@ -245,7 +340,7 @@ See source file '\inFileName' for details. \let\x\ProvidesPackage \fi \expandafter\endgroup -\x{luatexbase-mcb}[2010/05/27 v0.2a Callback management for LuaTeX] +\x{luatexbase-mcb}[2010/10/10 v0.3 Callback management for LuaTeX] % \end{macrocode} % % Make sure \luatex is used. @@ -259,14 +354,17 @@ See source file '\inFileName' for details. \fi \ifluatex\else \begingroup - \expandafter\ifx\csname PackageWarningNoLine\endcsname\relax - \def\x#1#2{\begingroup\newlinechar10 - \immediate\write16{Package #1 warning: #2}\endgroup} + \expandafter\ifx\csname PackageError\endcsname\relax + \def\x#1#2#3{\begingroup \newlinechar10 + \errhelp{#3}\errmessage{Package #1 error: #2}\endgroup} \else - \let\x\PackageWarningNoLine + \let\x\PackageError \fi \expandafter\endgroup - \x{luatexbase-mcb}{LuaTeX is required for this package. Aborting.} + \x{luatexbase-attr}{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.} \lltxb@mcb@AtEnd \expandafter\endinput \fi @@ -304,309 +402,280 @@ See source file '\inFileName' for details. % % \begin{macrocode} module('luatexbase', package.seeall) -luatexbase.provides_module({ - name = "luamcallbacks", +local err, warning, info = luatexbase.provides_module({ + name = "luatexbase-mcb", version = 0.2, date = "2010/05/12", description = "register several functions in a callback", - author = "Hans Hagen, Elie Roux and Manuel Pégourie-Gonnard", - copyright = "Hans Hagen, Elie Roux and Manuel Pégourie-Gonnard", + author = "Hans Hagen, Elie Roux and Manuel Pegourie-Gonnard", + copyright = "Hans Hagen, Elie Roux and Manuel Pegourie-Gonnard", license = "CC0", }) % \end{macrocode} % -% Shortcuts for error functions. +% \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 log = log or function(...) - luatexbase.module_log('luamcallbacks', string.format(...)) -end -local info = info or function(...) - luatexbase.module_info('luamcallbacks', string.format(...)) -end -local warning = warning or function(...) - luatexbase.module_warning('luamcallbacks', string.format(...)) -end -local err = err or function(...) - luatexbase.module_error('luamcallbacks', string.format(...)) -end +local callbacklist = callbacklist or { } % \end{macrocode} % -% \subsubsection{Initialisations} +% Numerical codes for callback types, and name to value association (the +% table keys are strings, the values are numbers). % -% \texttt{callbacklist} is the main list, that contains the callbacks as -% keys and a table of the registered functions a values. +% \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 callbacklist = callbacklist or { } +local callbacktypes = callbacktypes or { % \end{macrocode} % -% A table with the default functions of the created callbacks. See -% \texttt{create} for further informations. +% Section 4.1.1: file discovery callbacks. % % \begin{macrocode} -local lua_callbacks_defaults = { } + 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} % -% There are 4 types of callback: -% \begin{itemize} -% \item the ones taking a list of nodes and returning a boolean and -% eventually a new head (\texttt{list}) -% \item the ones taking datas and returning the modified ones -% (\texttt{data}) -% \item the ones that can't have multiple functions registered in them -% (\texttt{first}) -% \item the ones for functions that don't return anything (\texttt{simple}) -% \end{itemize} +% Section 4.1.2: file reading callbacks. % % \begin{macrocode} -local list = 1 -local data = 2 -local first = 3 -local simple = 4 + 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} % -% \texttt{callbacktypes} is the list that contains the callbacks as keys -% and the type (list or data) as values. +% Section 4.1.3: data processing callbacks. % % \begin{macrocode} -local callbacktypes = callbacktypes or { - buildpage_filter = simple, - token_filter = first, - pre_output_filter = list, - hpack_filter = list, - process_input_buffer = data, - mlist_to_hlist = list, - vpack_filter = list, - define_font = first, - open_read_file = first, - linebreak_filter = list, - post_linebreak_filter = list, - pre_linebreak_filter = list, - start_page_number = simple, - stop_page_number = simple, - start_run = simple, - show_error_hook = simple, - stop_run = simple, - hyphenate = simple, - ligaturing = simple, - kerning = data, - find_write_file = first, - find_read_file = first, - find_vf_file = data, - find_map_file = data, - find_format_file = data, - find_opentype_file = data, - find_output_file = data, - find_truetype_file = data, - find_type1_file = data, - find_data_file = data, - find_pk_file = data, - find_font_file = data, - find_image_file = data, - find_ocp_file = data, - find_sfd_file = data, - find_enc_file = data, - read_sfd_file = first, - read_map_file = first, - read_pk_file = first, - read_enc_file = first, - read_vf_file = first, - read_ocp_file = first, - read_opentype_file = first, - read_truetype_file = first, - read_font_file = first, - read_type1_file = first, - read_data_file = first, -} + process_input_buffer = data, + process_output_buffer = data, + token_filter = first, % \end{macrocode} % -% In Lua\TeX\ version 0.43, a new callback called |process_output_buffer| -% appeared, so we enable it. Test the version using the compat package for, -% well, compatibility. +% Section 4.1.4: node list processiong callbacks. % % \begin{macrocode} -if luatexbase.luatexversion > 42 then - callbacktypes["process_output_buffer"] = data -end + 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} % -% As we overwrite \texttt{callback.register}, we save it as -% \texttt{internalregister}. +% Section 4.1.5: information reporting callbacks. % % \begin{macrocode} -local internalregister = internalregister or callback.register + start_run = simple, + stop_run = simple, + start_page_number = simple, + stop_page_number = simple, + show_error_hook = simple, % \end{macrocode} % -% \subsubsection{Unsorted stuff} +% Section 4.1.6: font-related callbacks. % -% A simple function we'll use later to understand the arguments of the -% \texttt{create} function. It takes a string and returns the type -% corresponding to the string or nil. +% \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 function str_to_type(str) - if str == 'list' then - return list - elseif str == 'data' then - return data - elseif str == 'first' then - return first - elseif str == 'simple' then - return simple - else - return nil - end +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} % -% This function and the following ones are only internal. This one is the -% handler for the first type of callbacks: the ones that take a list head -% and return true, false, or a new list head. +% \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) +local function listhandler (name) return function(head,...) - local l = callbacklist[name] - if l then - local done = true - for _, f in ipairs(l) do - -- the returned value is either true or a new head plus true - rtv1, rtv2 = f.func(head,...) - if type(rtv1) == 'boolean' then - done = rtv1 - elseif type (rtv1) == 'userdata' then - head = rtv1 - end - if type(rtv2) == 'boolean' then - done = rtv2 - elseif type(rtv2) == 'userdata' then - head = rtv2 - end - if done == false then - err("function \"%s\" returned false in callback '%s'", - f.description, name) - end + local ret + local alltrue = true + for _, f in ipairs(callbacklist[name]) do + ret = f.func(head, ...) + if ret == false then + warn("function '%s' returned false\nin callback '%s'", + f.description, name) + break + end + if ret ~= true then + alltrue = false + head = ret end - return head, done - else - return head, false end + return alltrue and true or head end end % \end{macrocode} % -% The handler for callbacks taking datas and returning modified ones. +% Handler for |data| callbacks. % % \begin{macrocode} local function datahandler (name) - return function(data,...) - local l = callbacklist[name] - if l then - for _, f in ipairs(l) do - data = f.func(data,...) - end + return function(data, ...) + for _, f in ipairs(callbacklist[name]) do + data = f.func(data, ...) end return data end end % \end{macrocode} % -% This function is for the handlers that don't support more than one -% functions in them. In this case we only call the first function of the -% list. +% 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(...) - local l = callbacklist[name] - if l then - local f = l[1].func - return f(...) - else - return nil, false - end + return callbacklist[name][1].func(...) end end % \end{macrocode} % -% Handler for simple functions that don't return anything. +% Handler for |simple| callbacks. % % \begin{macrocode} local function simplehandler (name) return function(...) - local l = callbacklist[name] - if l then - for _, f in ipairs(l) do - f.func(...) - end + for _, f in ipairs(callbacklist[name]) do + f.func(...) end end end % \end{macrocode} % -% \subsubsection{Public functions} +% Finally, keep a handlers table for indexed access. % -% The main function. The signature is \texttt{add (name, -% func, description, priority)} with \texttt{name} being the name of the -% callback in which the function is added; \texttt{func} is the added -% function; \texttt{description} is a small character string describing the -% function, and \texttt{priority} an optional argument describing the -% priority the function will have. +% \begin{macrocode} +local handlers = { + [list] = listhandler, + [data] = datahandler, + [first] = firsthandler, + [simple] = simplehandler, +} +% \end{macrocode} % -% The functions for a callbacks are added in a list (in -% \texttt{callbacklist\\.callbackname}). If they have no -% priority or a high priority number, they will be added at the end of the -% list, and will be called after the others. If they have a low priority -% number, the will be added at the beginning of the list and will be called -% before the others. +% \subsubsection{Public functions for functions management} % -% Something that must be made clear, is that there is absolutely no -% solution for packages conflicts: if two packages want the top priority on -% a certain callback, they will have to decide the priority they will give -% to their function themselves. Most of the time, the priority is not needed. +% Add a function to a callback. First check arguments. % % \begin{macrocode} function add_to_callback (name,func,description,priority) if type(func) ~= "function" then - err("unable to add function, no proper function passed") - return + return err("unable to add function:\nno proper function passed") end if not name or name == "" then - err("unable to add function, no proper callback name passed") + err("unable to add function:\nno proper callback name passed") return elseif not callbacktypes[name] then - err("unable to add function, '%s' is not a valid callback", name) + 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', no proper description passed", + err("unable to add function to '%s':\nno proper description passed", name) return end - if priority_in_callback(name, description) ~= 0 then - warning("function '%s' already registered in callback '%s'", + 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 - if callbacktypes[name] == list then - internalregister(name, listhandler(name)) - elseif callbacktypes[name] == data then - internalregister(name, datahandler(name)) - elseif callbacktypes[name] == simple then - internalregister(name, simplehandler(name)) - elseif callbacktypes[name] == first then - internalregister(name, firsthandler(name)) - else - err("unknown callback type") - end + register_callback(name, handlers[callbacktypes[name]](name)) end end +% \end{macrocode} +% +% Actually register the function. +% +% \begin{macrocode} local f = { func = func, description = description, @@ -617,33 +686,35 @@ function add_to_callback (name,func,description,priority) elseif priority < 1 then priority = 1 end - if callbacktypes[name] == first and (priority ~= 1 or #l ~= 0) then - warning("several callbacks registered in callback '%s', " - .."only the first function will be active.", name) - end table.insert(l,priority,f) - log("inserting function '%s' at position %s in callback list for '%s'", +% \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 + info("inserting '%s'\nat position %s in '%s'", description, priority, name) end % \end{macrocode} % -% The function that removes a function from a callback. The signature is -% \texttt{remove (name, description)} with \texttt{name} being -% the name of callbacks, and description the description passed to -% \texttt{add}. +% 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, no proper callback name passed") + err("unable to remove function:\nno proper callback name passed") return elseif not callbacktypes[name] then - err("unable to remove function, '%s' is not a valid callback", name) + 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', no proper description passed", + "unable to remove function from '%s':\nno proper description passed", name) return end @@ -652,45 +723,84 @@ function remove_from_callback (name, description) 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 - table.remove(l,k) - log("removing function '%s' from '%s'",description,name) - if not next(l) then - callbacklist[name] = nil - if not lua_callbacks_defaults[name] then - internalregister(name, nil) - end - end - return + index = k + break + end + end + if not index then + err("unable to remove '%s'\nfrom '%s'", description, name) + return + end + table.remove(l, index) + info("removing '%s'\nfrom '%s'", description, name) + if table.maxn(l) == 0 then + callbacklist[name] = nil + if not lua_callbacks_defaults[name] then + register_callback(name, nil) end end - warning("unable to remove function '%s' from '%s'",description,name) + return end % \end{macrocode} % -% This function removes all the functions registered in a callback. +% Remove all the functions registered in a callback. Unregisters the +% callback handler unless the callback is user-defined. % % \begin{macrocode} -function reset_callback (name) +function reset_callback (name, make_false) if not name or name == "" then - err("unable to reset, no proper callback name passed") + err("unable to reset:\nno proper callback name passed") return elseif not callbacktypes[name] then - err("reset error, '%s' is not a valid callback", name) + err("unable to reset '%s':\nis not a valid callback", name) return end + info("resetting callback '%s'", name) + callbacklist[name] = nil if not lua_callbacks_defaults[name] then - internalregister(name, nil) + if make_false == true then + info("setting '%s' to false", name) + register_callback(name, false) + else + register_callback(name, nil) + end + end +end +% \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 l then - log("resetting callback list '%s'",name) - callbacklist[name] = nil + 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 % \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 @@ -705,24 +815,24 @@ end % \begin{macrocode} function create_callback(name, ctype, default) if not name then - err("unable to call callback, no proper name passed", name) + 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': " + 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', callback already exists", name) + err("unable to create callback '%s':\ncallback already exists", name) return nil end - local temp = str_to_type(ctype) - if not temp then - err("unable to create callback '%s', type '%s' undefined", name, ctype) + ctype = types[ctype] + if not ctype then + err("unable to create callback '%s':\ntype '%s' undefined", name, ctype) return nil end - ctype = temp + info("creating '%s' type %s", name, ctype) lua_callbacks_defaults[name] = default callbacktypes[name] = ctype end @@ -734,11 +844,11 @@ end % \begin{macrocode} function call_callback(name, ...) if not name then - err("unable to call callback, no proper name passed", name) + 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', unknown callback", name) + err("unable to call lua callback '%s':\nunknown callback", name) return nil end local l = callbacklist[name] @@ -746,92 +856,254 @@ function call_callback(name, ...) if not l then f = lua_callbacks_defaults[name] else - if callbacktypes[name] == list then - f = listhandler(name) - elseif callbacktypes[name] == data then - f = datahandler(name) - elseif callbacktypes[name] == simple then - f = simplehandler(name) - elseif callbacktypes[name] == first then - f = firsthandler(name) - else + f = handlers[callbacktypes[name]](name) + if not f then err("unknown callback type") + return end end return f(...) end % \end{macrocode} % -% This function tells if a function has already been registered in a -% callback, and gives its current priority. The arguments are the name of -% the callback and the description of the function. If it has already been -% registered, it gives its priority, and if not it returns false. +% That's all folks! % % \begin{macrocode} -function priority_in_callback (name, description) - if not name or name == "" - or not callbacktypes[name] - or not description then - return 0 - end - local l = callbacklist[name] - if not l then return 0 end - for p, f in pairs(l) do - if f.description == description then - return p - end - end - return 0 +%</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} % -% Finally we -% overwrite \texttt{callback.register} so that it outputs an error. +% Create a callback, and check that the managment functions work with this +% callback too. % % \begin{macrocode} -callback.register = function () -err("function callback.register has been deleted by luamcallbacks, " -.."please use luatexbase.add_to_callback instead.") +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} % -% That's all folks! +% 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} -%</lua> +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} % -% \section{Test files} +% 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 few basic tests for Plain and LaTeX. +% 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 -\luatexbase@directlua{ - local function one(head,...) - texio.write_nl("I'm number 1") - return head, true - end - - local function two(head,...) - texio.write_nl("I'm number 2") - return head, true - end - - local function three(head,...) - texio.write_nl("I'm number 3") - return head, true - end - - luatexbase.add_to_callback("hpack_filter",one,"my sample function one",1) - luatexbase.add_to_callback("hpack_filter",two,"my sample function two",2) - luatexbase.add_to_callback("hpack_filter",three,"my sample function three",1) - - luatexbase.remove_from_callback("hpack_filter","my sample function three") +\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 |