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{{#invoke:example|hello}} → Hello World!{{#invoke:example|hello_to|Fred}} → Hello, Fred!{{#invoke:example|count_fruit|bananas=5|apples=12}} → I have 5 bananas and 12 apples{{#invoke:example|test|3|abc=2|4}} → table - attempt to return the whole table of parameters at once; just gives the word 'table'{{#invoke:example|get_parameters|3|abc=2|4}} → 3 4 7 2 14 - shows that no distinction has to be made between abc being a string variable and being a numerical variable: its value 2 can be used in a computation as well as in a concatenation. In wikitext this is similar, except that in Lua concatenation requires dot pairs, while wikitext requires triple braces around parameter names and parameter numbers, and a parser function for computations. Both allow, in different ways, the distinction between the value of the variable abcdef and the concatenation of the values of the variables abc and def.{{#invoke:example|get_parameters1|3|abc=2|4}} → 3 4 7 2 14
local p = {}; --All lua modules on Wikipedia must begin by defining a variable --that will hold their externally accessible functions. --Such variables can have whatever name you want and may --also contain various data as well as functions. p.hello = function( frame ) --Add a function to "p". --Such functions are callable in Wikipedia --via the #invoke command. --"frame" will contain the data that Wikipedia --sends this function when it runs. -- 'Hello' is a name of your choice. The same name needs to be referred to when the module is used. local str = "Hello World!" --Declare a local variable and set it equal to --"Hello World!". return str --This tells us to quit this function and send the information in --"str" back to Wikipedia. end -- end of the function "hello" function p.hello_to(frame)-- Add another function local name = frame.args[1] -- To access arguments passed to a module, use `frame.args` -- `frame.args[1]` refers to the first unnamed parameter -- given to the module return "Hello, " .. name .. "!" -- `..` concatenates strings. This will return a customized -- greeting depending on the name given, such as "Hello, Fred!" end function p.test(frame) return frame end function p.count_fruit(frame) local num_bananas = frame.args.bananas -- Named arguments ({{#invoke:Example|count_fruit|foo=bar}}) are likewise local num_apples = frame.args.apples -- accessed by indexing `frame.args` by name (`frame.args["bananas"]`, or) -- equivalently `frame.args.bananas`. return 'I have ' .. num_bananas .. ' bananas and ' .. num_apples .. ' apples' -- Like above, concatenate a bunch of strings together to produce -- a sentence based on the arguments given. end local function lucky(a, b) -- One can define custom functions for use. Here we define a function 'lucky' that has two inputs a and b. The names are of your choice. if b == 'yeah' then -- Condition: if b is the string 'yeah'. Strings require quotes. Remember to include 'then'. return a .. ' is my lucky number.' -- Outputs 'a is my lucky number.' if the above condition is met. The string concatenation operator is denoted by 2 dots. else -- If no conditions are met, i.e. if b is anything else, output specified on the next line. 'else' should not have 'then'. return a -- Simply output a. end -- The 'if' section should end with 'end'. end -- As should 'function'. function p.get_parameters(frame) pars = frame:getParent().args -- This line allows template parameters to be used in this code easily. The equal sign is used to define variables. 'pf' can be replaced with a word of your choice. local pars = frame.args -- This line allows parameters from {{#invoke:}} to be used easily. 'pars' can be replaced with a word of your choice. local p1 = pars[1] -- first unnamed parameter. local p2 = pars[2] -- Second unnamed parameter. local abc = pars.abc -- Named parameter. return p1..' '..p2..' '..p1+p2..' '..abc..' '..(p1+p2)*abc end function p.get_parametersgp(frame) local pars = frame:getParent().args -- This line allows template parameters to be used in this code easily. The equal sign is used to define variables. 'pf' can be replaced with a word of your choice. local p1 = pars[1] -- first unnamed parameter. local p2 = pars[2] -- Second unnamed parameter. local abc = pars.abc -- Named parameter. return p1..' '..p2..' '..p1+p2..' '..abc..' '..(p1+p2)*abc end function p.get_parameters1(frame) local pars = frame.args -- This line allows parameters from {{#invoke:}} to be used easily. 'pars' can be replaced with a word of your choice. local p1 = pars[1] -- first unnamed parameter. local p2 = pars[2] -- Second unnamed parameter. local abc = pars.abc -- Named parameter. return p1..' '..p2..' '..p1+p2..' '..abc..' '..(p1+p2)*abc end function p.Name2(frame) -- The next five lines are mostly for convenience only and can be used as is for your module. The output conditions start on line 20. local pf = frame:getParent().args -- This line allows template parameters to be used in this code easily. The equal sign is used to define variables. 'pf' can be replaced with a word of your choice. local f = frame.args -- This line allows parameters from {{#invoke:}} to be used easily. 'f' can be replaced with a word of your choice. local M = f[1] or pf[1] -- f[1] and pf[1], which we just defined, refer to the first parameter. This line shortens them as 'M' for convenience. You could use the original variable names. local m = f[2] or pf[2] -- Second shortened as 'm local l = f.lucky or pf.lucky -- A named parameter 'lucky' is shortend as l. Note that the syntax is different from unnamed parameters.'. if m == nil then -- If the second parameter is not used. return 'Lonely' -- Outputs the string 'Lonely' if the first condition is met. elseif M > m then -- If the first condition is not met, this line tests a second condition: if M is greater than m. return lucky(M - m, l) -- If the condition is met, the difference is calculated and passed to the self defined function along with l. The output depends on whether l is set to 'yeah'. else return 'Be positive!' end end return p --All modules end by returning the variable containing their functions to Wikipedia. -- Now we can use this module by calling {{#invoke: Example | hello }}, -- {{#invoke: Example | hello_to | foo }}, or {{#invoke:Example|count_fruit|bananas=5|apples=6}} -- Note that the first part of the invoke is the name of the Module's wikipage, -- and the second part is the name of one of the functions attached to the -- variable that you returned. -- The "print" function is not allowed in Wikipedia. All output is accomplished -- via strings "returned" to Wikipedia. 
