lua function call overhead lua function call overhead

It doesnt have many gotchas. I think it really depends on the language and on the function. While the c and c++ compilers can inline a lot of functions, this is not the case fo Felicia Hagler - via Google, In the middle of a big move and so far Jay Casey has been immensely helpful to us with all the details! Or is it something else? If you need a debugger, I recommend checking out. Incnis Mrsi (talk) 22:46, 9 January 2014 (UTC). Also explains why the uselang=qqq hack doesn't work to show the scribunto messages. They have lots of options for moving. try: with open("foo.txt") as f: Mr. Stradivarius talk 09:47, 11 November 2013 (UTC), I've updated Wikipedia:Lua/Modules/Overview using a Lua module to generate a table from various simple cut and paste data. Frietjes (talk) 00:03, 4 July 2013 (UTC), At the moment we have the {{lua talk}} template to use on talk pages of templates converted to Lua. First lets set up the environment and test that it works, start by install gopher-lua: Secondly lets create a minimal implementation: lua.NewState() creates our Lua VM, and it is though L (*lua.LState) we will interact with Lua in the future. --Iantresman (talk) 00:06, 12 December 2013 (UTC). now i wanted to translate Category:Pages with script errors in bn language. Mr. Stradivarius talk 01:15, 29 October 2013 (UTC), How well does Scribunto defend itself against DoS, or possibly XSS, but especially DoS as we are dealing with a Turing-complete language? Writing the code in it feels like writing pseudocode/prototyping. If youre writing a game and want to make it possible for people to create mods, many of your players are likely to know Lua thanks to such games as Minecraft, Factorio, Garrys Mod, World of Warcraft, Roblox and. Easy to start using, the interface is user friendly and feels similar to C++ standard library. Wnt (talk) 15:52, 22 January 2014 (UTC), Wikipedia:Lua/To do, a page you substantially contributed to, has been nominated for deletion. L.DoString runs the Lua code in the VM. This can result in slow compilation times, unreadable error messages and some interfaces are not that friendly (e.g. In Module:Sidebar, I extended the boilerplate further to allow a third way, invoking the module from a template and passing args in explicitly (instead of using whatever args were passed to the template), like {{#invoke: Navbar | arg1 = foo | arg2 = bar}}. -DePiep (talk) 11:51, 22 March 2013 (UTC). Lori Baker - via Google. Ive used LuaDists CMake build scripts for Lua for many years, but LuaDist authors have stopped supporting newer Lua versions. They are iteration functions, so they add the overhead of a function call to each loop iteration. Johnuniq (talk) 09:37, 7 October 2013 (UTC). What can I do to increase the performance of a Lua Page content can be retrieved with the getContent () method of the title object. Best Mr. Stradivarius talk 10:42, 27 March 2013 (UTC), You've got it pretty much right. Also, this page should explain that it is not possible to move a module to another namespace or vice versa, except doc pages (I think). Is there a programme wizard who can help see if I've done something stupid? We have an even split on people who do personal testing in Sandbox/ and people who do it in User: At this point, either of us could pull up stakes and migrate to the other pretty easily. However, sometimes that is just not enough and an embedded language can be the solution. I've created a new request page for Lua scripts at Wikipedia:Lua requests. Lua adjusts the number of arguments to the number of parameters, Our areas of expertise include Commercial Moving Services, Warehousing, Document Shredding and Storage Solutions. To learn Lua, read Programming in Lua by Roberto Ierusalimschy. There is still lots of work to do of course, But it's a start TheDJ (talk contribs) 22:18, 18 March 2013 (UTC). I didn't use Special:ExpandTemplates, though - I really did just forget my curly braces. I get an error message when I use it. If you create a local object inside the coroutine and store the reference to it in C++. I would have been able to continue contributing to these and other interesting templates. There are some practical functions to convert and check lua.LValue objects. {\displaystyle d=3^{(n/2000)}.} Will your logo be here as well?. Calling Lua code is done through L.CallByParam, which takes a parameters object, P, and arguments as variadic parameters. Its stable. You dont need to compile Lua code, which means that you can change parts of your program/game logic without recompiling and even without reloading your program. I was going to deploy it on Template:Year in other calendars/testcases, but in my preview it runs out of time by the time it gets to the last test. I want to output wikitext like this: I have previously done that and it worked well, but when the text between the tags is more varied, something breaks. The function is followed by the arguments, in order. that is, to call o.foo adding o as a first extra argument. Casey Moving Systems is family owned and has been servicing Northern California for over 25 years. Mr. Stradivarius talk 16:45, 29 March 2013 (UTC), I decided to implement a Lua replacement for the innards of {{Repeat}} as a learning project for my first Lua module. All values in Lua can be stored in variables, used as arguments when calling functions, and returned as the result of their execution. OUR MISSION. If a conflict can not be resolved in a satisfactory manner, the function should throw an error to signify this; returning false or nil will result in that value being written to the key. I'd rather see useful LUA links. Debresser (talk) 10:57, 8 December 2013 (UTC), Is the "Wikipedia namespaces" infobox necessary top right? At the moment, we have three patterns in naming a module sandbox page: I suggest that is one too much. but this fact has no relevance to Lua programmers. But with the banning of the print function and the extra steps to validate the lua code in Wiki, I can't tell if the lua.org tutorial truly helpful to me as I don't know how to convert all those examples to comply with MediaWiki's lua standard. Village Pump (policy)#Protection and management of scripts? If anyone could help me to work this out I'd be very grateful. 1 time resty -e '' We can see theres overhead of about 11 milliseconds on this machine. The syntax of the template sends another template as parameter. Each layer of "shell templates" (to #invoke a Lua function) also increases the expansion depth by about +2 levels of the 41-level limit (shows "41/40"). Lua is a language with implicitly dynamic data types. Greetings Stephan Kulla (talk) 15:54, 19 May 2013 (UTC), (Sorry for writing here. --Iantresman (talk) 18:29, 7 December 2013 (UTC), I used to be an above average template editor, making significant contributions to even such intricate template as Ambox and Fix. I'm currently using the following function to get template arguments. lua.LVAsBool(v LValue) - Convert to bool, nil and false becomes false. Thanks! In brief, the categories I set up were pre-alpha, alpha, beta, release, and protected. FT2(Talk|email) 02:07, 20 March 2013 (UTC), I found this guide for learning how to code Lua, may be of help or use www.lua.org/pil/contents.html#P1, I feel like I must have reinvented the wheel here, but I copied Template:Tlx to Template:Mlx with minor modifications, so we can type, and get {{#invoke:ConvertNumeric|decToHex|99 33}}, It would be good if someone could look this over for any flaws before it gets cascade-protected by something. Text formatting (bold, italics) breaks when the ''/''' tags are not closed for each argument. After the function call, New versions come out once in a while, but you can comfortably stay on Lua 5.2 not loose much. An auto sizing callstack will allocate and release callstack pages on demand which will ensure the minimum amount of memory is in use at any time. WebLua scripts have the same capability with calling MMF events. For example, it is not printing the string "mw.site.currentVersion", and only two "mw.site.stats" table rows, which might suggest it is not recursing properly, or perhaps something else. I just quickly sorted out the present Lua modules to Wikipedia:Lua/Modules/Overview. Wnt thinks that the template should use the "style" type (with a yellow background), and I think it should use the "notice" type (with a grey background). I think that this is less effective than it could be, however. ?0" here but useful if omit above. Time-delay formula: The initial tests show a time-delay formula as roughly delay=3^(n/2000) seconds, where n is the number of parameters passed, and for n=6,000, the delay has been 3^3 or 27 seconds, or for n=7,000 then the delay has been 3^3.5 or 47 seconds. So tonight I put together Module:Unsubst, which can be used to do the same thing without all the limitations of {{unsubst}}. At Module:DisplayLuaTableContents I see numerous loops as, , but I learned that strings are immutable and hence this assignment is rather costly. I don't know, but with some of these things being transcluded on every page in the wiki, and having elaborate powers to write anything they can slip by the interface, we should be wary of security holes, and the first step is to know quickly and certainly which are a unit, I think. Comments appreciated. This is typically done with a copyright template placed on your user page though you might want to modify one of them to specify that it only applies to Lua modules. the colon operator. For instance, consider the following function, to increment a global counter. This function has 1 as its default argument; that is, the call incCount (), without arguments, increments count by one. When you call incCount () , Lua first initializes n with nil ; the or results in its second operand; and as a result Lua assigns a default 1 to n . Basically, you need to tell Lua explicitly that something youve created in the coroutine needs to outlive this coroutine (and this is done with lua_xmove). WebDue to the short-circuiting behavior of or, it will generally impose little additional overhead at call-time: local soundit; do local sounds; function soundit (x) sounds = sounds or { a = "ay" , b = "bee" , c = "see" , . } assert ( type (x) == "string" ) return sounds [x] end end Perhaps li in a list or tr in a table? Support for calling a parser function is coming soon with frame:callParserFunction, or you could do it today by passing the markup to frame:preprocess. {{. Calling the LValue.Type() returns the corresponding LValueType. *, I'd like to find out which mw.site library options are available, and print their value, without having to specify each one individually, ie. Needs study to guarantee correctness! lua However, after writing up Module:Hex, which hex dumps the contents of strings, I was looking at the talk page when I noticed that the hex-dump of the contents of a strip marker (the example with UNIQ QINU) are changing every single time I hit the Talk tab or browser reload button to reload the page, even when I'm completely logged out with scripts disabled! WebYou can call a template from a Lua module using frame:expandTemplate. This concept might be extended to support more than one memory location: Lua Performance Tips Lua n The XLua object also has a substantial MMF Interface for directly querying and modifying game objects and state Its a road map for learning Lua and my advice for how to integrate it with C/C++ code. What is the equivalent of {{fullurl:page name}}? But what I'd like to ask now is: as a matter of general policy, does it ever make sense to link from a module that is in such widespread use that it needs to be protected to the current copy of another module? For optional arguments the L.Opt(n int, default T) functions can be used. is there a better way to do this? Youre unlikely to run into performance issues, unless youre making a AA/AAA game or a complex simulation program. To maintain similarity with other sandbox pages (in template space and user space), I propose: If we agree on this, we can encourage/discourage patterns. WebThe Lua interpreter offers two hooks for debug purposes: typedef void (*lua_CHFunction) (lua_Function func, char *file, int line); extern lua_CHFunction lua_callhook; typedef void (*lua_LHFunction) (int line); extern lua_LHFunction lua_linehook; The first one is called whenever the interpreter enters or leaves a function. However, in the example where SomeClass is returned as a local variable, you wont need to do this - if you just load the script.lua, it would execute some_class.lua when you call require (it would only do this if another script didnt call it, otherwise it would return a cached SomeClass variable). For example, Module:Navbar contains the code: In what case would frame not be equal to mw.getCurrentFrame()? You can write entire games in Lua without ever touching C/C++. WebWhen iterating a table, the function overhead from ipairs does not justify it's use. WebThe Redis Lua execution context always provides a singleton instance of an object named redis . -- Sameboat - (talk) 07:07, 18 March 2013 (UTC), Thank Dragons flight for clearing something for me. Frietjes (talk) 16:17, 30 October 2013 (UTC). This doesn't, which I was hoping would be equivalent: And, how do I do the reverse, and convert mw.site.currentVersion to the string "mw.site.currentVersion"? You can call a function with a number of arguments different from Similarly to the previous advice, when defining classes (e.g. The same can be said about making your program expandable with plugins. See http://godoc.org/github.com/yuin/gopher-lua#LTable for the LTable Go API. These snippets of Python and Lua are roughly equivalent. The problem with 3rd party bindings is that they usually tend to get unmaintained or only support a specific version of the library. Similar to avoiding use of prior utility templates, when writing other utility templates, I would recommend to use the direct #invoke to access Lua functions from a utility template. -Wikid77 (talk) 19:29, 22 March 2013 (UTC), When moving a module there is no redirect left behind and existing invocations should be fixed. This will make your life easier, because you would be able to write less binding code and be able to stay inside Lua code as much as possible. How you divide up your code among different Dont put too much code into one script - its easy to separate everything into smaller scripts. An expression like o:foo(x) sign in Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Almost all of us to be a lot better about putting comments up front in the module and/or documentation saying what the heck our modules are FOR. If you used classes as globals (which Ive seen in many tutorials and real code), you might have a script like this: Suppose that you didnt execute some_class.lua first (which defines a global SomeClass). WebBut when you create thou sands of small tables, the combined overhead can be signic ant. The Lua version has some differences from the current template, so I would like to get others' comments before making the switch. That way it would be obvious straight away which templates have been converted, and would help advertise the fact that we have this neat new programming language available and that we need people to convert existing templates over. You couldn't keep track of your old experiments, and my experience is that yes, I. http://godoc.org/github.com/yuin/gopher-lua, http://github.com/otm/embedding-lua-in-go, http://godoc.org/github.com/yuin/gopher-lua#LTable. Does this apply if you are accessing the module from another Lua module, and not directly from a wiki page? I am trying to implement {{Horizontal timeline}} as a module. During operation, in the event that any functions share the same name, a table will be created with that name and the conflicting functions will be stored there using the name of the script they came from, such that with two scripts foo and bar, both containing the function foo, you would end up with the functions foo.foo and foo.bar. a function definition has a conventional syntax; If this behavior is not suitable for your usecase, a custom handler function for resolving conflicting functions can be used by passing a function as an optional second argument. When calling a function, This was possible because the wikimarkup language was very intuitive, and easy to understand even for the layman. Automatic transclusion of protection templates was added. P:S Creating separate module for template2 in above example is not feasible because I am trying to reduce the number of template substitution and writing separate modules would defeat the purpose.--Jayarathina (talk) 05:20, 24 December 2013 (UTC). Its simple. Its a good starting point for making your own CMake build for Lua, though (or if you use older versions of Lua, they work well). WebFunctions used by a Lua program can be defined both in Lua and in C (or in any other language used by the host application). Do I need to use %f and remove the trailing zeros with string.match or string.gsub? Currently it is misleading advising to check for double redirects. Everyone took really good care of our things. For instance, all library functions are written in C; There was a problem preparing your codespace, please try again. -happy5214 14:32, 15 March 2013 (UTC), You own the copyright, you can grant whatever licenses you want (in addition, as you say, to the CC-BY-SA license that you've already granted). Cya. Page contents not supported in other languages. The simplest way to time some Lua code is to use the time command with the resty command. Wnt (talk) 23:14, 21 March 2013 (UTC), I have run many timing tests, to compare using shell templates which contain #invoke versus direct use of {#invoke:}, and for tiny templates, such as string-handling functions, the template versions often ran upto 50% slower than direct #invoke of each tiny Lua function. Fantastic help. For instance, if we have a function like. A [6] question at Module:Redirect reminded me of a remarkable statement by @Wikid77: that updating some Lua modules can cause 7 million pages to be reformatted on the WP:Job queue. You can even create small domain specific languages thanks to Luas syntax sugar. I was wondering if there is a way to improve the performance. Caution is desirable because it is very confusing for anyone reading the code later if tostring() does not do what it normally does, however the following is the idea. Use Git or checkout with SVN using the web URL. What functions should be called in C++ gameloop from Affects Lua, templates & parser functions: Again, the time-delay overhead, to pass thousands of parameters, not only affects the Lua #invoke interface, it extends the same exponential time-delay slowdown in passing parameters to templates as well as "|x=" branch-choices in a #switch function (which also runs 27 seconds to process 6,000 branches). There are still a few things I'm not sure about, though. Check out this engine for making Zelda-likes for inspiration of how to write game code in Lua. Is this the right place for Lua programming queries? You just compile a bunch of C files, link with the library and youre ready to go - you dont need to rewrite half of your program/game or make your build script 10 times more difficult. Johnuniq (talk) 06:53, 11 October 2013 (UTC), Doesn't Wikipedia's version of Lua allow the GetURL function (or equivalent)? Is these Lua performance tips still accurate? : r/lua - Reddit in Lua and functions defined in C. As we have seen in other examples, Can they be rewritten in Lua, perhaps? The related, but separate issue, for speed of #invoke, can quicken every use of Lua, if 1.22wmf1 successfully doubles the speed of each #invoke. --Iantresman (talk) 11:31, 9 December 2013 (UTC), Can modules "call" other modules? Can someone make a nice SpecialPages adjustment? Functions are the main mechanism for abstraction of statements However, I found that returning mw.message.newRawMessage("{{User:Wnt/Templates/Sandbox2}}"):parse() produces a timestamp that never changes when the page invoking the module is reloaded, because the page transcluded is not checked at all. Now the tab "Modules" does not show all modules, and does not have a 'next page' link. Writing code like this will become better with new #embed directive in future C/C++ versions, e.g. 1 Answer Sorted by: 3 I would generally recommend to avoid making high volume calls into Lua. You can divide up your code into separate functions. In Lua, all arrays are 1-indexed, however t[0] is still valid but that would result in the lenght of the array to be off-by-one. Technical 13 (talk) 12:12, 9 May 2013 (UTC). I was just trying to return those hex tables via loadData and seem to have run into a nasty surprise. If nothing happens, download GitHub Desktop and try again. how can i do this (on which module, i find this Category for translation). I tried to start learning Lua and immediately hit the wall after the "hello, world" part and all I got afterward are "script error". and expressions in Lua. What I'm trying to do is much more complicated, see Module:Convert/makeunits, but is the same issue. --Rotpunkt (talk) 12:35, 1 May 2013 (UTC), Hello, I'm wondering if there is currently a module that counts elements on a page. itch.io was written with it and it compiles to vanilla Lua. 7.3 Hooks Sandboxing is easy. So the idea is the next one: But lua has a specific way to treat weblink and it is right now impossible to use a web address as a string. See a simple example of how to build Lua with CMake and use it with sol2 here. Anomie 03:36, 1 November 2013 (UTC), User:Wnt and I have had a little disagreement over the type parameter of the {{lua}} template. (At least script error should be shown when print function is detected.) If nothing happens, download Xcode and try again. How much do function calls impact performance? This is a matter of implementation of the compiler or runtime (and its options) and cannot be said with any certainty. E.g. If you'd like to make a request, please do that too! WebLua Functions - A function is a group of statements that together perform a task. with nil arguments removed. string.format('%f %f %f', 0.00001, 1.2, 3) => 0.000010 1.200000 3.000000, string.format('%g %g %g', 0.00001, 1.2, 3) => 1e-05 1.2 3, This page was last edited on 4 February 2023, at 15:13. The LTable type can be used for emulating namespaces and classes. Vanilla Lua, the latest version, otherwise. Is there a way to obtain a list (array) of all pages with a prefix (e.g. with nil arguments removed. DePiep (talk) 23:55, 21 May 2015 (UTC). A tag already exists with the provided branch name. Isnt it great? Your life will be easier if you have a small C/C++ API. The redis instance enables the script to interact with the Redis server that's running Your help pointing to ways to improve is welcome. lua.LVIsFalse(v LValue) - Returns true if nil or false. It stays global and doesnt get collected by a GC until it has been set to nil. Thats basically all youll ever need to know about Lua. Note: Lua isnt zero-indexed, so the first function argument is fetched with L.ToInt(1), second argument with L.ToInt(2). Dcoetzee 23:09, 23 February 2013 (UTC), There's a discussion at the technical pump currently about where to put code that you're experimenting with; as a result Module:Sandbox has been created. - basically everything else that doesnt interact with low-level OS APIs much. For instance, all library functions are written in C; ), You dont need a specialized IDE or tools to write Lua comfortably. If you only want to call some C/C++ functions from Lua (or some small Lua functions from C/C++) - use Lua C API. The parameters object takes three important parameters: Fn - the lua.LFunction to call Nret - The number of returned values Protect - If protect is true an error is returned, otherwise a panic will occur. The docs are fantastic too. If an argument to a function can be of more then one type the L.CheckTypes(n int, types LValueType) function can be used to check and yield an error to the user. I am a repeat customer and have had two good experiences with them. ), The disadvantage of course is that bugfixes in modules like Redirect don't get passed on. If you notice that your C++ function has a huge overhead because of Lua calls, consider using this pattern: If you dont use local to define/init a variable, it becomes a global by default. Link/Create testcases link for Module pages. Providing global relocations solutions, storage and warehousing platforms and destruction plans. Is it a good idea to deviate from the template standard of calling pages with testcases, tests for the module namespace? Makyen(talk) 04:02, 8 May 2014 (UTC), I've heard for quite a while that the Lua scripts only run when the page is parsed, which rules out many interactive features but is efficient. thank you. To get automatic errors the L.Check(n int) family of functions can be used; They throw a Lua error if the type check fails. The approach of Module:Sandbox - having every user put scripts into a common receptacle - seems unworkable. . You can do procedural, functional, OO programming. Since Lua has lexical scope at the block level rather than the function level, this works similarly to the way Python calls __exit__. Thanks. Gut feeling is usually wrong. Immediately afterward it gives you another line of codes which I have absolutely no idea where to insert it to make it functional at all. NeoVim, which uses Lua scripts for user script code. Reinterpreting The Lua Interpreter | Hackaday At least one such template will be beyond the 500 EPFs/page limit in 2015.