Module:String2

 require('strict');
 localp={}

 p.trim=function(frame)
 returnmw.text.trim(frame.args[1]or"")
 end

 p.sentence=function(frame)
 -- {{lc:}} is strip-marker safe, string.lower is not.
 frame.args[1]=frame:callParserFunction('lc',frame.args[1])
 returnp.ucfirst(frame)
 end

 p.ucfirst=function(frame)
 locals=frame.args[1];
 ifnotsor''==sors:match('^%s+$')then-- when <s> is nil, empty, or only whitespace
 returns;-- abandon because nothing to do
 end

 s=mw.text.trim(frame.args[1]or"")
 locals1=""

 localprefix_patterns_t={-- sequence of prefix patterns
 '^127円[^127円]*UNIQ%-%-%a+%-%x+%-QINU[^127円]*127円',-- stripmarker
 '^([%*;:#]+)',-- various list markup
 '^(\'\'\'*)',-- bold / italic markup
 '^(%b<>)',-- html-like tags because some templates render these
 '^(&%a+;)',-- html character entities because some templates render these
 '^(&#%d+;)',-- html numeric (decimal) entities because some templates render these
 '^(&#x%x+;)',-- html numeric (hexadecimal) entities because some templates render these
 '^(%s+)',-- any whitespace characters
 '^([%(%)%-%+%?%.%%!~!@%$%^&_={}/`,‘’„""ʻ|\"\'\\]+)',-- miscellaneous punctuation
 }

 localprefixes_t={};-- list, bold/italic, and html-like markup, & whitespace saved here

 localfunctionprefix_strip(s)-- local function to strip prefixes from <s>
 for_,patterninipairs(prefix_patterns_t)do-- spin through <prefix_patterns_t> 
 ifs:match(pattern)then-- when there is a match
 localprefix=s:match(pattern);-- get a copy of the matched prefix
 table.insert(prefixes_t,prefix);-- save it
 s=s:sub(prefix:len()+1);-- remove the prefix from <s>
 returns,true;-- return <s> without prefix and flag; force restart at top of sequence because misc punct removal can break stripmarker
 end
 end
 returns;-- no prefix found; return <s> with nil flag
 end

 localprefix_removed;-- flag; boolean true as long as prefix_strip() finds and removes a prefix

 repeat-- one by one remove list, bold/italic, html-like markup, whitespace, etc from start of <s>
 s,prefix_removed=prefix_strip(s);
 until(notprefix_removed);-- until <prefix_removed> is nil

 s1=table.concat(prefixes_t);-- recreate the prefix string for later reattachment

 localfirst_text=mw.ustring.match(s,'^%[%[[^%]]+%]%]');-- extract wikilink at start of string if present; TODO: this can be string.match()?

 localupcased;
 iffirst_textthen
 iffirst_text:match('^%[%[[^|]+|[^%]]+%]%]')then-- if <first_text> is a piped link
 upcased=mw.ustring.match(s,'^%[%[[^|]+|%W*(%w)');-- get first letter character
 upcased=mw.ustring.upper(upcased);-- upcase first letter character
 s=mw.ustring.gsub(s,'^(%[%[[^|]+|%W*)%w','%1'..upcased);-- replace
 else-- here when <first_text> is a wikilink but not a piped link
 upcased=mw.ustring.match(s,'^%[%[%W*%w');-- get '[[' and first letter
 upcased=mw.ustring.upper(upcased);-- upcase first letter character
 s=mw.ustring.gsub(s,'^%[%[%W*%w',upcased);-- replace; no capture needed here
 end

 elseifs:match('^%[%S+%s+[^%]]+%]')then-- if <s> is a ext link of some sort; must have label text
 upcased=mw.ustring.match(s,'^%[%S+%s+%W*(%w)');-- get first letter character
 upcased=mw.ustring.upper(upcased);-- upcase first letter character
 s=mw.ustring.gsub(s,'^(%[%S+%s+%W*)%w','%1'..upcased);-- replace

 elseifs:match('^%[%S+%s*%]')then-- if <s> is a ext link without label text; nothing to do
 returns1..s;-- reattach prefix string (if present) and done

 else-- <s> is not a wikilink or ext link; assume plain text
 upcased=mw.ustring.match(s,'^%W*%w');-- get the first letter character
 upcased=mw.ustring.upper(upcased);-- upcase first letter character
 s=mw.ustring.gsub(s,'^%W*%w',upcased);-- replace; no capture needed here
 end

 returns1..s;-- reattach prefix string (if present) and done
 end


 p.title=function(frame)
 -- http://grammar.yourdictionary.com/capitalization/rules-for-capitalization-in-titles.html
 -- recommended by The U.S. Government Printing Office Style Manual:
 -- "Capitalize all words in titles of publications and documents,
 -- except a, an, the, at, by, for, in, of, on, to, up, and, as, but, or, and nor."
 localalwayslower={['a']=1,['an']=1,['the']=1,
 ['and']=1,['but']=1,['or']=1,['for']=1,
 ['nor']=1,['on']=1,['in']=1,['at']=1,['to']=1,
 ['from']=1,['by']=1,['of']=1,['up']=1}
 localres=''
 locals=mw.text.trim(frame.args[1]or"")
 localwords=mw.text.split(s," ")
 fori,sinipairs(words)do
 -- {{lc:}} is strip-marker safe, string.lower is not.
 s=frame:callParserFunction('lc',s)
 ifi==1oralwayslower[s]~=1then
 s=mw.getContentLanguage():ucfirst(s)
 end
 words[i]=s
 end
 returntable.concat(words," ")
 end

 -- findlast finds the last item in a list
 -- the first unnamed parameter is the list
 -- the second, optional unnamed parameter is the list separator (default = comma space)
 -- returns the whole list if separator not found
 p.findlast=function(frame)
 locals=mw.text.trim(frame.args[1]or"")
 localsep=frame.args[2]or""
 ifsep==""thensep=", "end
 localpattern=".*"..sep.."(.*)"
 locala,b,last=s:find(pattern)
 ifathen
 returnlast
 else
 returns
 end
 end

 -- stripZeros finds the first number and strips leading zeros (apart from units)
 -- e.g "0940" -> "940"; "Year: 0023" -> "Year: 23"; "00.12" -> "0.12"
 p.stripZeros=function(frame)
 locals=mw.text.trim(frame.args[1]or"")
 localn=tonumber(string.match(s,"%d+"))or""
 s=string.gsub(s,"%d+",n,1)
 returns
 end

 -- nowiki ensures that a string of text is treated by the MediaWiki software as just a string
 -- it takes an unnamed parameter and trims whitespace, then removes any wikicode
 p.nowiki=function(frame)
 localstr=mw.text.trim(frame.args[1]or"")
 returnmw.text.nowiki(str)
 end

 -- split splits text at boundaries specified by separator
 -- and returns the chunk for the index idx (starting at 1)
 -- #invoke:String2 |split |text |separator |index |true/false
 -- #invoke:String2 |split |txt=text |sep=separator |idx=index |plain=true/false
 -- if plain is false/no/0 then separator is treated as a Lua pattern - defaults to plain=true
 p.split=function(frame)
 localargs=frame.args
 ifnot(args[1]orargs.txt)thenargs=frame:getParent().argsend
 localtxt=args[1]orargs.txtor""
 iftxt==""thenreturnnilend
 localsep=(args[2]orargs.sepor""):gsub('"','')
 localidx=tonumber(args[3]orargs.idx)or1
 localplain=(args[4]orargs.plainor"true"):sub(1,1)
 plain=(plain~="f"andplain~="n"andplain~="0")
 localsplittbl=mw.text.split(txt,sep,plain)
 ifidx<0thenidx=#splittbl+idx+1end
 returnsplittbl[idx]
 end

 -- val2percent scans through a string, passed as either the first unnamed parameter or |txt=
 -- it converts each number it finds into a percentage and returns the resultant string.
 p.val2percent=function(frame)
 localargs=frame.args
 ifnot(args[1]orargs.txt)thenargs=frame:getParent().argsend
 localtxt=mw.text.trim(args[1]orargs.txtor"")
 iftxt==""thenreturnnilend
 localfunctionv2p(x)
 x=(tonumber(x)or0)*100
 ifx==math.floor(x)thenx=math.floor(x)end
 returnx.."%"
 end
 txt=txt:gsub("%d[%d%.]*",v2p)-- store just the string
 returntxt
 end

 -- one2a scans through a string, passed as either the first unnamed parameter or |txt=
 -- it converts each occurrence of 'one ' into either 'a ' or 'an ' and returns the resultant string.
 p.one2a=function(frame)
 localargs=frame.args
 ifnot(args[1]orargs.txt)thenargs=frame:getParent().argsend
 localtxt=mw.text.trim(args[1]orargs.txtor"")
 iftxt==""thenreturnnilend
 txt=txt:gsub(" one "," a "):gsub("^one","a"):gsub("One ","A "):gsub("a ([aeiou])","an %1"):gsub("A ([aeiou])","An %1")
 returntxt
 end

 -- findpagetext returns the position of a piece of text in a page
 -- First positional parameter or |text is the search text
 -- Optional parameter |title is the page title, defaults to current page
 -- Optional parameter |plain is either true for plain search (default) or false for Lua pattern search
 -- Optional parameter |nomatch is the return value when no match is found; default is nil
 p._findpagetext=function(args)
 -- process parameters
 localnomatch=args.nomatchor""
 ifnomatch==""thennomatch=nilend
 --
 localtext=mw.text.trim(args[1]orargs.textor"")
 iftext==""thenreturnnilend
 --
 localtitle=args.titleor""
 localtitleobj
 iftitle==""then
 titleobj=mw.title.getCurrentTitle()
 else
 titleobj=mw.title.new(title)
 end
 --
 localplain=args.plainor""
 ifplain:sub(1,1)=="f"thenplain=falseelseplain=trueend
 -- get the page content and look for 'text' - return position or nomatch
 localcontent=titleobjandtitleobj:getContent()
 returncontentandmw.ustring.find(content,text,1,plain)ornomatch
 end
 p.findpagetext=function(frame)
 localargs=frame.args
 localpargs=frame:getParent().args
 fork,vinpairs(pargs)do
 args[k]=v
 end
 ifnot(args[1]orargs.text)thenreturnnilend
 -- just the first value
 return(p._findpagetext(args))
 end

 -- returns the decoded url. Inverse of parser function {{urlencode:val|TYPE}}
 -- Type is:
 -- QUERY decodes + to space (default)
 -- PATH does no extra decoding
 -- WIKI decodes _ to space
 p._urldecode=function(url,type)
 url=urlor""
 type=(type=="PATH"ortype=="WIKI")andtype
 returnmw.uri.decode(url,type)
 end
 -- {{#invoke:String2|urldecode|url=url|type=type}}
 p.urldecode=function(frame)
 returnmw.uri.decode(frame.args.url,frame.args.type)
 end

 -- what follows was merged from Module:StringFunc

 -- helper functions
 p._GetParameters=require('Module:GetParameters')

 -- Argument list helper function, as per Module:String
 p._getParameters=p._GetParameters.getParameters

 -- Escape Pattern helper function so that all characters are treated as plain text, as per Module:String
 functionp._escapePattern(pattern_str)
 returnmw.ustring.gsub(pattern_str,"([%(%)%.%%%+%-%*%?%[%^%$%]])","%%%1")
 end

 -- Helper Function to interpret boolean strings, as per Module:String
 p._getBoolean=p._GetParameters.getBoolean

 --[[
 Strip

 This function Strips characters from string

 Usage:
 {{#invoke:String2|strip|source_string|characters_to_strip|plain_flag}}

 Parameters
 	source: The string to strip
 	chars: The pattern or list of characters to strip from string, replaced with ''
 	plain: A flag indicating that the chars should be understood as plain text. defaults to true.

 Leading and trailing whitespace is also automatically stripped from the string.
 ]]
 functionp.strip(frame)
 localnew_args=p._getParameters(frame.args,{'source','chars','plain'})
 localsource_str=new_args['source']or''
 localchars=new_args['chars']or''or'characters'
 source_str=mw.text.trim(source_str)
 ifsource_str==''orchars==''then
 returnsource_str
 end
 locall_plain=p._getBoolean(new_args['plain']ortrue)
 ifl_plainthen
 chars=p._escapePattern(chars)
 end
 localresult
 result=mw.ustring.gsub(source_str,"["..chars.."]",'')
 returnresult
 end

 --[[
 Match any
 Returns the index of the first given pattern to match the input. Patterns must be consecutively numbered.
 Returns the empty string if nothing matches for use in {{#if:}}

 Usage:
 	{{#invoke:String2|matchAll|source=123 abc|456|abc}} returns '2'.

 Parameters:
 	source: the string to search
 	plain: A flag indicating that the patterns should be understood as plain text. defaults to true.
 	1, 2, 3, ...: the patterns to search for
 ]]
 functionp.matchAny(frame)
 localsource_str=frame.args['source']orerror('The source parameter is mandatory.')
 locall_plain=p._getBoolean(frame.args['plain']ortrue)
 fori=1,math.hugedo
 localpattern=frame.args[i]
 ifnotpatternthenreturn''end
 ifmw.ustring.find(source_str,pattern,1,l_plain)then
 returntostring(i)
 end
 end
 end

 --[[--------------------------< H Y P H E N _ T O _ D A S H >--------------------------------------------------

 Converts a hyphen to a dash under certain conditions. The hyphen must separate
 like items; unlike items are returned unmodified. These forms are modified:
 	letter - letter (A - B)
 	digit - digit (4-5)
 	digit separator digit - digit separator digit (4.1-4.5 or 4-1-4-5)
 	letterdigit - letterdigit (A1-A5) (an optional separator between letter and
 		digit is supported – a.1-a.5 or a-1-a-5)
 	digitletter - digitletter (5a - 5d) (an optional separator between letter and
 		digit is supported – 5.a-5.d or 5-a-5-d)

 any other forms are returned unmodified.

 str may be a comma- or semicolon-separated list

 ]]
 functionp.hyphen_to_dash(str,spacing)
 if(str==nilorstr=='')then
 returnstr
 end

 localaccept

 str=mw.text.decode(str,true)-- replace html entities with their characters; semicolon mucks up the text.split

 localout={}
 locallist=mw.text.split(str,'%s*[,;]%s*')-- split str at comma or semicolon separators if there are any

 for_,iteminipairs(list)do-- for each item in the list
 item=mw.text.trim(item)-- trim whitespace
 item,accept=item:gsub('^%(%((.+)%)%)$','%1')
 ifaccept==0andmw.ustring.match(item,'^%w*[%.%-]?%w+%s*[%-–—]%s*%w*[%.%-]?%w+$')then-- if a hyphenated range or has endash or emdash separators
 ifitem:match('^%a+[%.%-]?%d+%s*%-%s*%a+[%.%-]?%d+$')or-- letterdigit hyphen letterdigit (optional separator between letter and digit)
 item:match('^%d+[%.%-]?%a+%s*%-%s*%d+[%.%-]?%a+$')or-- digitletter hyphen digitletter (optional separator between digit and letter)
 item:match('^%d+[%.%-]%d+%s*%-%s*%d+[%.%-]%d+$')or-- digit separator digit hyphen digit separator digit
 item:match('^%d+%s*%-%s*%d+$')or-- digit hyphen digit
 item:match('^%a+%s*%-%s*%a+$')then-- letter hyphen letter
 item=item:gsub('(%w*[%.%-]?%w+)%s*%-%s*(%w*[%.%-]?%w+)','%1–%2')-- replace hyphen, remove extraneous space characters
 else
 item=mw.ustring.gsub(item,'%s*[–—]%s*','–')-- for endash or emdash separated ranges, replace em with en, remove extraneous whitespace
 end
 end
 table.insert(out,item)-- add the (possibly modified) item to the output table
 end

 localtemp_str=table.concat(out,','..spacing)-- concatenate the output table into a comma separated string
 temp_str,accept=temp_str:gsub('^%(%((.+)%)%)$','%1')-- remove accept-this-as-written markup when it wraps all of concatenated out
 ifaccept~=0then
 temp_str=str:gsub('^%(%((.+)%)%)$','%1')-- when global markup removed, return original str; do it this way to suppress boolean second return value
 end
 returntemp_str
 end

 functionp.hyphen2dash(frame)
 localstr=frame.args[1]or''
 localspacing=frame.args[2]or' '-- space is part of the standard separator for normal spacing (but in conjunction with templates r/rp/ran we may need a narrower spacing

 returnp.hyphen_to_dash(str,spacing)
 end

 -- Similar to [[Module:String#endswith]]
 functionp.startswith(frame)
 return(frame.args[1]:sub(1,frame.args[2]:len())==frame.args[2])and'yes'or''
 end

 -- Implements [[Template:Isnumeric]]
 functionp.isnumeric(frame)
 locals=frame.args[1]orframe:getParent().args[1]
 localboolean=(frame.args.booleanorframe:getParent().args.boolean)=='true'
 iftype(s)=='string'andmw.getContentLanguage():parseFormattedNumber(s)then
 returnbooleanand1ors
 end
 returnbooleanand0or''
 end

 -- Checks if a value in a group of numbers is not an interger.
 -- Allows usage of an |empty= parameter to allow empty values to be skipped.
 functionp.isInteger(frame)
 localvalues=frame.argsorframe:getParent().args
 localallow_empty=frame.args.emptyorframe:getParent().args.empty

 for_,valueinipairs(values)do
 -- Trim spaces
 value=valueandvalue:gsub("^%s*(.-)%s*$","%1")
 ifvalue==""orvalue==nilthen
 ifnotallow_emptythen
 returnfalse-- Empty values are not allowed
 end
 else
 value=tonumber(value)
 ifnot(type(value)=="number"andvalue==math.floor(value))then
 returnfalse
 end
 end
 end

 returntrue
 end

 -- Returns an error found in a string.
 functionp.getError(frame)
 localtext=frame.args[1]orframe:getParent().args[1]
 localerror_message=text:match('(<strong class="error">.-</strong>)')
 returnerror_messageornil
 end

 returnp