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diff --git a/doc/context/sources/general/manuals/luametatex/luametatex-differences.tex b/doc/context/sources/general/manuals/luametatex/luametatex-differences.tex deleted file mode 100644 index 403f1a029..000000000 --- a/doc/context/sources/general/manuals/luametatex/luametatex-differences.tex +++ /dev/null @@ -1,411 +0,0 @@ -% language=us runpath=texruns:manuals/luametatex - -\environment luametatex-style - -\startcomponent luametatex-differences - -\startchapter[reference=differences,title={Differences with \LUATEX}] - -As \LUAMETATEX\ is a leaner and meaner \LUATEX. This means that substantial parts and -dependencies are gone: quite some font code, all backend code with related frontend -code and of course image and font inclusion. There is also new functionality which -makes for less lean but in the end we still have less, also in terms of dependencies. -This chapter will discuss what is gone. We start with the primitives that were dropped. - -\starttabulate[|l|pl|] -\BC fonts \NC \type {\letterspacefont} - \type {\copyfont} - \type {\expandglyphsinfont} - \type {\ignoreligaturesinfont} - \type {\tagcode} - \type {\leftghost} - \type {\rightghost} - \NC \NR -\BC backend \NC \type {\dviextension} - \type {\dvivariable } - \type {\dvifeedback} - \type {\pdfextension} - \type {\pdfvariable } - \type {\pdffeedback} - \type {\dviextension} - \type {\draftmode} - \type {\outputmode} - \NC \NR -\BC dimensions \NC \type {\pageleftoffset} - \type {\pagerightoffset} - \type {\pagetopoffset} - \type {\pagebottomoffset} - \type {\pageheight} - \type {\pagewidth} - \NC \NR -\BC resources \NC \type {\saveboxresource} - \type {\useboxresource} - \type {\lastsavedboxresourceindex} - \type {\saveimageresource} - \type {\useimageresource} - \type {\lastsavedimageresourceindex} - \type {\lastsavedimageresourcepages} - \NC \NR -\BC positioning \NC \type {\savepos} - \type {\lastxpos} - \type {\lastypos} - \NC \NR -\BC directions \NC \type {\textdir} - \type {\linedir} - \type {\mathdir} - \type {\pardir} - \type {\pagedir} - \type {\bodydir} - \type {\pagedirection} - \type {\bodydirection} - \NC \NR -\BC randomizer \NC \type {\randomseed} - \type {\setrandomseed} - \type {\normaldeviate} - \type {\uniformdeviate} - \NC \NR -\BC utilities \NC \type {\synctex} - \NC \NR -\BC extensions \NC \type {\latelua} - \type {\lateluafunction} - \type {\openout} - \type {\write} - \type {\closeout} - \type {\openin} - \type {\read} - \type {\readline} - \type {\closein} - \type {\ifeof} - \NC \NR -\BC control \NC \type {\suppressfontnotfounderror} - \type {\suppresslongerror} - \type {\suppressprimitiveerror} - \type {\suppressmathparerror} - \type {\suppressifcsnameerror} - \type {\suppressoutererror} - \type {\mathoption} - \NC \NR -\BC system \NC \type {\primitive} - \type {\ifprimitive} - \type {\formatname} - \NC \NR -\BC ignored \NC \type {\long} - \type {\outer} - \type {\mag} - \NC \NR -\stoptabulate - -The math machinery has been overhauled stepwise. In the process detailed control -has been added but later some of that got removed or replaced. The engine now -assumes that \OPENTYPE\ fonts are used but you do need to set up the engine -properly, something that has to be done with respect to fonts anyway. By enabling -and|/|disabling certain features you can emulate the traditional engine. Font -parameters no longer are taken from the traditional parameters when they are not -set. We just assume properly passed so called math constants and quite a few new -ones have been added. - -The resources and positioning primitives are actually useful but can be defined -as macros that (via \LUA) inject nodes in the input that suit the macro package -and backend. The three||letter direction primitives are gone and the numeric -variants are now leading. There is no need for page and body related directions -and they don't work well in \LUATEX\ anyway. We only have two directions left. -Because we can hook in \LUA\ functions that get information about what is expected -(consumer or provider) there are plenty possibilities for adding functionality -using this scripting language. - -The primitive related extensions were not that useful and reliable so they have -been removed. There are some new variants that will be discussed later. The \type -{\outer} and \type {\long} prefixes are gone as they don't make much sense -nowadays and them becoming dummies opened the way to something new: control -sequence properties that permit protection against as well as controlled -overloading of definitions. I don't think that (\CONTEXT) users will notice these -prefixes being gone. The definition and parsing related \type {\suppress..} -features are now default and can't be changed so related primitives are gone. - -The \type {\shipout} primitive does no ship out but just erases the content of -the box unless of course that has happened already in another way. A macro -package should implement its own backend and related shipout. Talking of backend, -the extension primitives that relate to backends can be implemented as part of a -backend design using generic whatsits. There is only one type of whatsit now. In -fact we're now closer to original \TEX\ with respect to the extensions. - -The \type {img} library has been removed as it's rather bound to the backend. The -\type {slunicode} library is also gone. There are some helpers in the string -library that can be used instead and one can write additional \LUA\ code if -needed. There is no longer a \type {pdf} backend library but we have an up to -date \PDF\ parsing library on board. - -In the \type {node}, \type {tex} and \type {status} library we no longer have -helpers and variables that relate to the backend. The \LUAMETATEX\ engine is in -principle \DVI\ and \PDF\ unaware. There are, as mentioned, only generic whatsit -nodes that can be used for some management related tasks. For instance you can -use them to implement user nodes. More extensive status information is provided -in the overhauled status library. All libraries have additional functionality and -names of functions have been normalized (for as far as possible). - -The margin kern nodes are gone and we now use regular kern nodes for them. As a -consequence there are two extra subtypes indicating the injected left or right -kern. The glyph field served no real purpose so there was no reason for a special -kind of node. - -The \KPSE\ library is no longer built|-|in, but one can use an external \KPSE\ -library, assuming that it is present on the system, because the engine has a so -called optional library interface to it. Because there is no backend, quite some -file related callbacks could go away. The following file related callbacks -remained (till now): - -\starttyping -find_write_file find_format_file open_data_file -\stoptyping - -The callbacks related to errors are changed: - -\starttyping -intercept_tex_error intercept_lua_error -show_error_message show_warning_message -\stoptyping - -There is a hook that gets called when one of the fundamental memory structures -gets reallocated. - -\starttyping -trace_memory -\stoptyping - -When you use the overload protect mechanisms, a callback can be plugged in to handle -exceptions: - -\starttyping -handle_overload -\stoptyping - -The (job) management hooks are kept: - -\starttyping -process_jobname -start_run stop_run wrapup_run -pre_dump -start_file stop_file -\stoptyping - -Because we use a more generic whatsit model, there is a new callback: - -\starttyping -show_whatsit -\stoptyping - -Because tracing boxes now reports a lot more information, we have a plug in for -detail: - -\starttyping -get_attribute -\stoptyping - -Being the core of extensibility, the typesetting callbacks of course stayed. This -is what we ended up with: - -\startalign[flushleft,nothyphenated] -\tt \cldcontext{table.concat(table.sortedkeys(callbacks.list), ", ")} -\stopalign - -As in \LUATEX\ font loading happens with the following callback. This time it -really needs to be set because there is no built|-|in font loader. - -\starttyping -define_font -\stoptyping - -There are all kinds of subtle differences in the implementation, for instance we -no longer intercept \type {*} and \type {&} as these were already replaced long -ago in \TEX\ engines by command line options. Talking of options, only a few are -left. All input goes via \LUA, even the console. One can program a terminal if -needed. - -We took our time for reaching a stable state in \LUATEX. Among the reasons is the -fact that most was experimented with in \CONTEXT, which we can adapt to the -engine as we go. It took many years to decide what to keep and how to do things. -Of course there are places when things can be improved but that most likely only -happens in \LUAMETATEX. Contrary to what is sometimes suggested, the -\LUATEX|-|\CONTEXT\ \MKIV\ combination (assuming matched versions) has been quite -stable. It made no sense otherwise. Most \CONTEXT\ functionality didn't change -much at the user level. Of course there have been issues, as is natural with -everything new and beta, but we have a fast update cycle. - -The same is true for \LUAMETATEX\ and \CONTEXT\ \LMTX: it can be used for -production as usual and in practice \CONTEXT\ users tend to use the beta -releases, which proves this. Of course, if you use low level features that are -experimental you're on your own. Also, as with \LUATEX\ it might take many years -before a long term stable is defined. The good news is that, when the source code -has become part of the \CONTEXT\ distribution, there is always a properly -working, more or less long term stable, snapshot. - -The error reporting subsystem has been redone quite a bit but is still -fundamentally the same. We don't really assume interactive usage but if someone -uses it, it might be noticed that it is not possible to backtrack or inject -something. Of course it is no big deal to implement all that in \LUA\ if needed. -It removes a system dependency and makes for a bit cleaner code. In \CONTEXT\ we -quit on an error simply because one has to fix source anyway and runs are fast -enough. Logging provides more detail and new primitives can be used to prevent -clutter in tracing (the more complex a macro package becomes, the more extreme -tracing becomes). - -There are new primitives as well as some extensions to existing primitive -functionality. These are described in following chapters but there might be -hidden treasures in the binary. If you locate them, don't automatically assume -them to stay, some might be part of experiments! There are for instance a few -csname related definers, we have integer and dimension constants, the macro -argument parser can be brought in tolerant mode, the repertoire of conditionals -has been extended, some internals can be controlled (think of normalization of -lines, hyphenation etc.), and macros can be protected against user overload. Not -all is discussed in detail in this manual but there are introductions in the -\CONTEXT\ distribution that explain them. But the \TEX\ kernel is of course -omnipresent. - -\startluacode - -local luametatex = tex.primitives() -local luatex = table.load("luatex-primitives.lua") - -if not luatex then - local tex = "\\starttext \\ctxlua {table.save(tex.jobname .. '.lua',tex.primitives())} \\stoptext" - - io.savedata("luatex-primitives.tex", tex) - - os.execute("context --luatex --once luatex-primitives") - - luatex = table.load("luatex-primitives.lua") -end - - -if luatex and luametatex then - - local match = string.match - - local found = { } - - local function collect(index) - if index then - local data = index.entries - for i=1,#data do - found[match(data[i].list[1][1],"\\tex%s*{(.-)}") or ""] = true - end - -- inspect(found) - end - end - - collect(structures.registers.collected and structures.registers.collected.texindex) - collect(structures.registers.collected and structures.registers.collected.luatexindex) - - luatex = table.tohash(luatex) - luametatex = table.tohash(luametatex) - - -- context.page() - - context("The following primitives are available in \\LUATEX\\ but not in \\LUAMETATEX. ") - context("Some of these are emulated in \\CONTEXT.") - - context.blank() - context.startcolumns { n = 2 } - for k, v in table.sortedhash(luatex) do - if not luametatex[k] then - if not found[k] then - context.dontleavehmode() - end - context.type(k) - context.crlf() - end - end - context.stopcolumns() - context.blank() - - -- context.page() - - context("The following primitives are available in \\LUAMETATEX\\ only. In the meantime ") - context("the \\LUAMETATEX\\ code base is so different from \\LUATEX\\ that backporting ") - context("is no longer reasonable.") - - context.blank() - context.startcolumns { n = 2 } - for k, v in table.sortedhash(luametatex) do - if not luatex[k] then - if not found[k] then - context.dontleavehmode() - context.llap("\\infofont[todo] ") - end - context.type(k) - context.crlf() - end - end - context.stopcolumns() - context.blank() - -end - -\stopluacode - -As part of a bit more consistency some function names also changed. Names with an -\type {_} got that removed (as that was the minority). It's easy to provide a -back mapping if needed (just alias the functions). - -{\em Todo: only mention the \LUATEX\ ones.} - -\starttabulate[|l|l|l|l|] -\DB library \BC old name \BC new name \BC comment \NC \NR -\TB -\NC language \NC clear_patterns \NC clearpatterns \NC \NR -\NC \NC clear_hyphenation \NC clearhyphenation \NC \NR -\NC mplib \NC italcor \NC italic \NC \NR -\NC \NC pen_info \NC peninfo \NC \NR -\NC \NC solve_path \NC solvepath \NC \NR -\NC texio \NC write_nl \NC writenl \NC old name stays \NC \NR -\NC node \NC protect_glyph \NC protectglyph \NC \NR -\NC \NC protect_glyphs \NC protectglyphs \NC \NR -\NC \NC unprotect_glyph \NC unprotectglyph \NC \NR -\NC \NC unprotect_glyphs \NC unprotectglyphs \NC \NR -\NC \NC end_of_math \NC endofmath \NC \NR -\NC \NC mlist_to_hlist \NC mlisttohlist \NC \NR -\NC \NC effective_glue \NC effectiveglue \NC \NR -\NC \NC has_glyph \NC hasglyph \NC \NR -\NC \NC first_glyph \NC firstglyph \NC \NR -\NC \NC has_field \NC hasfield \NC \NR -\NC \NC copy_list \NC copylist \NC \NR -\NC \NC flush_node \NC flushnode \NC \NR -\NC \NC flush_list \NC flushlist \NC \NR -\NC \NC insert_before \NC insertbefore \NC \NR -\NC \NC insert_after \NC insertafter \NC \NR -\NC \NC last_node \NC lastnode \NC \NR -\NC \NC is_zero_glue \NC iszeroglue \NC \NR -\NC \NC make_extensible \NC makeextensible \NC \NR -\NC \NC uses_font \NC usesfont \NC \NR -\NC \NC is_char \NC ischar \NC \NR -\NC \NC is_direct \NC isdirect \NC \NR -\NC \NC is_glyph \NC isglyph \NC \NR -\NC \NC is_node \NC isnode \NC \NR -\NC token \NC scan_keyword \NC scankeyword \NC \NR -\NC \NC scan_keywordcs \NC scankeywordcs \NC \NR -\NC \NC scan_int \NC scanint \NC \NR -\NC \NC scan_real \NC scanreal \NC \NR -\NC \NC scan_float \NC scanfloat \NC \NR -\NC \NC scan_dimen \NC scandimen \NC \NR -\NC \NC scan_glue \NC scanglue \NC \NR -\NC \NC scan_toks \NC scantoks \NC \NR -\NC \NC scan_code \NC scancode \NC \NR -\NC \NC scan_string \NC scanstring \NC \NR -\NC \NC scan_argument \NC scanargument \NC \NR -\NC \NC scan_word \NC scanword \NC \NR -\NC \NC scan_csname \NC scancsname \NC \NR -\NC \NC scan_list \NC scanlist \NC \NR -\NC \NC scan_box \NC scanbox \NC \NR -\LL -\stoptabulate - -It's all part of trying to make the code base consistent but it is sometimes a -bit annoying. However, that's why we develop this engine independent of the -\LUATEX\ code base. It's anyway a change that has been on my todo list for quite -a while because those inconsistencies annoyed me. It might take some years to -get all done. - -\stopchapter - -\stopcomponent - |