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This Lua module is used onapproximately 459,000 pages. To avoid major disruption and server load, any changes should be tested in the module's/sandbox or/testcases subpages, or in your ownmodule sandbox. The tested changes can be added to this page in a single edit. Consider discussing changes on thetalk page before implementing them.
Extracts all parameters from a data template and returns them as a Lua table. This function is only usable from other Lua modules; invoke it usingrequire('Module:CountryData').gettable(parameters).
The first parameter is theframe of the invoking module; the second is the country or other entity to get the data of. The optional third parameter is a table of parameters to pass into the data template; this may, for example, include|age= or|mw=, which are used in the values of some sports alias parameters. E.g.,
The function returns an empty table if a data template does not exist or does not conform to thestandard structure.
getalias
If used from wikicode, this function returns the value of a single field in a data template. The first parameter is the country or other entity whose data to return; the second is the name of the field. For example,{{#invoke:CountryData|getalias|France|flag alias}} → Flag of France.svg. The other parameters are|variant= to return a variant parameter value, with fallback to the main field value if the variant does not exist, and|def= for the fallback output if the wanted data template or field does not exist, the default for which is a literal "nil".
Note: This is likely not quicker than wikicode-only alternatives such as{{getalias}} and{{getalias2}}, because it transcludes the data template from Lua and converts it to a Lua table using the above function, picks the wanted parameter name, and returns it to wikicode, whereas other templates perform two simple non-Lua transclusions to get, in most cases, the same result. The Lua version does have the advantage that using it with a non-existing country data template returns "nil" (or the value of|def=) rather than a redlink to the data template. See a comparison of the four atUser:SiBr4/Flagg tests#Lua-based getalias.
gettemplate
This function concatenates the fields of a data template into a string similar to what you get when transcluding it directly. It can be compared with a direct transclusion to test if a template is being converted to Lua correctly:
{{#tag:pre|{{Country data France}}}}{{#tag:pre|{{#invoke:CountryData|gettemplate|France}}}}
gives
{{ {{{1}}}| alias = France| flag alias = Flag of France.svg| flag alias-1790 = Flag of France (1790–1794).svg| flag alias-1794 = Flag of France (1794–1815, 1830–1958).svg| flag alias-1814 = Flag of the Kingdom of France (1814-1830).svg| flag alias-1830 = Flag of France (1794–1815, 1830–1958).svg| flag alias-1848 = Drapeau france 1848.svg| flag alias-1848a = Drapeau france 1848.svg| flag alias-1848b = Flag of France (1794–1815, 1830–1958).svg| flag alias-1974 = Flag of France (lighter variant).svg| flag alias-naval = Civil and Naval Ensign of France.svg| flag alias-naval-1790 = Flag of French-Navy-Revolution.svg| flag alias-air force = Flag of France.svg| link alias-air force = French Air and Space Force| flag alias-coast guard = French Maritime Gendarmerie racing stripe.svg| border-coast guard = | link alias-coast guard = French Maritime Gendarmerie| flag alias-army = Flag of France.svg| link alias-army = French Army| link alias-naval = French Navy| flag alias-navy = Civil and Naval Ensign of France.svg| link alias-navy = French Navy| size = | name = | altlink = | variant = }}
{{ {{{1}}}| altlink = | flag alias-naval-1790 = Flag of French-Navy-Revolution.svg| link alias-coast guard = French Maritime Gendarmerie| border-coast guard = | flag alias-1848 = Drapeau france 1848.svg| flag alias = Flag of France.svg| variant = | flag alias-1814 = Flag of the Kingdom of France (1814-1830).svg| flag alias-1830 = Flag of France (1794–1815, 1830–1958).svg| alias = France| flag alias-1794 = Flag of France (1794–1815, 1830–1958).svg| flag alias-army = Flag of France.svg| flag alias-naval = Civil and Naval Ensign of France.svg| flag alias-navy = Civil and Naval Ensign of France.svg| flag alias-1848b = Flag of France (1794–1815, 1830–1958).svg| name = | size = | flag alias-1848a = Drapeau france 1848.svg| link alias-naval = French Navy| flag alias-1974 = Flag of France (lighter variant).svg| link alias-air force = French Air and Space Force| link alias-army = French Army| flag alias-coast guard = French Maritime Gendarmerie racing stripe.svg| flag alias-1790 = Flag of France (1790–1794).svg| flag alias-air force = Flag of France.svg| link alias-navy = French Navy}}
Note that, like with all Lua tables, the order of entries is not preserved, so the parameters are mixed up.
localp={}localmostUsed=mw.loadData('Module:CountryData/summary')localfunctiongetcontents(frame,country,params)returnframe:expandTemplate({title="Country data "..country;args=params})endfunctionp.getcachedtable(frame,country,params)country=mostUsed.redirects[country]orcountryifparamsandnext(params)thenreturnp.gettable(frame,country,params)end-- Uses mw.loadData to cache data for the most-used templatesifmostUsed.pages[country]thenlocalcache=mw.loadData('Module:CountryData/cache'..mostUsed.pages[country])ifcache.data[country]thenreturncache.data[country]endend-- if not in cachereturnp.gettable(frame,country,params)endfunctionp.gettable(frame,country,params)--Returns the parameters of a country data template as a Lua table--If not a valid data template, return empty tablelocalbool,s=pcall(getcontents,frame,country,paramsor{})ifbooland(string.find(s,"^%{%{ *%{%{%{1")orstring.find(s,"^%{%{safesubst: *%{%{%{1"))then--Replace parameter delimiters with arbitrary control characters--to avoid clashes if param values contain equals/pipe signss=string.gsub(s,"|([^|=]-)=","\1\1%1\2")s=string.gsub(s,"}}%s*$","\1")--Loop over string and add params to tablelocalpart={}forparinstring.gmatch(s,"\1[^\1\2]-\2[^\1\2]-\1")dolocalk=string.match(par,"\1%s*(.-)%s*\2")localv=string.match(par,"\2%s*(.-)%s*\1")ifvandnot(v==""andstring.find(k,"^flag alias"))thenpart[k]=vendendreturnpartelsereturn{}endendfunctionp.getalias(frame)--Returns a single parameter value from a data templatelocalpart=p.gettable(frame,frame.args[1])ifframe.args.variantthenreturntostring(part[frame.args[2].."-"..frame.args.variant]orpart[frame.args[2]]orframe.args.def)elsereturntostring(part[frame.args[2]]orframe.args.def)endendfunctionp.gettemplate(frame)--For testing, recreates the country data from the created Lua table--Get data tablelocaldata=p.gettable(frame,frame.args[1])--Concatenate fields into a template-like stringlocalout="{{ {{{1}}}"fork,vinpairs(data)doout=out.."\n| "..k.." = "..vendreturnout.."\n}}"endreturnp
