Modul:ISO15924

Modul:ISO15924

Version vom 10. März 2020, 11:47 Uhr von imported>PerfektesChaos (2020-03-10)
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Die Dokumentation für dieses Modul kann unter Modul:ISO15924/Doku erstellt werden

local ISO15924 = { suite   = "ISO15924",
                   serial  = "2020-03-10",
                   item    = 71584769,
                   statics = "codes" }
--[=[
ISO 15924 support for scripting systems
* fetch()
* getLanguageScript()
* getScripts()
* isCJK()
* isRTL()
* isScript()
* isTrans()
* scriptName()
* showScript()
* showScripts()
* testScripts()
* failsafe()
]=]
local Failsafe  = ISO15924
local GlobalMod = ISO15924
local Unicode



ISO15924.Text    = { }
ISO15924.Unicode = { }
Unicode = ISO15924.Unicode
Unicode.RomanN = { bef = {   [ 32 ] = true,
                            [ 160 ] = true,
                           [ 8239 ] = true,
                             [ 40 ] = true,
                             [ 45 ] = true,
                             [ 91 ] = true
                         },
                   dig = { [ 73 ] = true,    -- I
                           [ 86 ] = true,    -- V
                           [ 88 ] = true,    -- X
                           [ 76 ] = true,    -- L
                           [ 67 ] = true,    -- C
                           [ 68 ] = true,    -- D
                           [ 77 ] = true     -- M
                         },
                   fol = {   [ 32 ] = true,
                            [ 160 ] = true,
                           [ 8239 ] = true,
                             [ 41 ] = true,
                             [ 44 ] = true,
                             [ 46 ] = true,
                             [ 93 ] = true
                         } }
ISO15924.Commons = { "cjk",
                     "iso639script",
                     "reverse",
                     "rtl",
                     "trans",
                     "unicodes" }



local foreignModule = function ( access, advanced, append, alt, alert )
    -- Fetch global module
    -- Precondition:
    --     access    -- string, with name of base module
    --     advanced  -- true, for require(); else mw.loadData()
    --     append    -- string, with subpage part, if any; or false
    --     alt       -- number, of wikidata item of root; or false
    --     alert     -- true, for throwing error on data problem
    -- Postcondition:
    --     Returns whatever, probably table
    -- 2019-10-29
    local storage = access
    local finer = function ()
                      if append then
                          storage = string.format( "%s/%s",
                                                   storage,
                                                   append )
                      end
                  end
    local fun, lucky, r, suited
    if advanced then
        fun = require
    else
        fun = mw.loadData
    end
    GlobalMod.globalModules = GlobalMod.globalModules or { }
    suited = GlobalMod.globalModules[ access ]
    if not suited then
        finer()
        lucky, r = pcall( fun,  "Module:" .. storage )
    end
    if not lucky then
        if not suited  and
           type( alt ) == "number"  and
           alt > 0 then
            suited = string.format( "Q%d", alt )
            suited = mw.wikibase.getSitelink( suited )
            GlobalMod.globalModules[ access ] = suited or true
        end
        if type( suited ) == "string" then
            storage = suited
            finer()
            lucky, r = pcall( fun, storage )
        end
        if not lucky and alert then
            error( "Missing or invalid page: " .. storage, 0 )
        end
    end
    return r
end -- foreignModule()



local function fill( accumulate, assign, append )
    -- Copy external sequence into local collection
    -- Precondition:
    --     accumulate  -- table, with relevant definitions
    --     assign      -- table, with assigned definitions
    --     append      -- table, if code names to be appended to entries
    if type( assign ) == "table" then
        local e
        for k, v in pairs( assign ) do
            if type( v ) == "table" then
                e = { }
                for kk, vv in pairs( v ) do
                    table.insert( e, vv )
                end -- for kk, vv
                if append then
                     for i = 1, #append do
                        table.insert( e, append[ i ] )
                    end -- for i
                end
                table.insert( accumulate, e )
            end
        end -- for k, v
    end
end -- fill()



local function fulfil( ask, attribute )
    -- Check whether script has a certain attribute
    -- Precondition:
    --     ask  -- string, with language or script code
    --     attribute  -- string, with "cjk" or "rtl"
    -- Returns true, if matchin
    local got = ISO15924.fetch( attribute )
    local r
    if type( got ) == "table" then
        local n = #ask
        local script
        if n == 4 then
            script = ask
        elseif n < 4 then
            script = ISO15924.getLanguageScript( ask )
        else
            script = ask:match( "^%a%a%a?%-(%a%a%a%a)$" )
            if not script then
                script = ask:match( "^(%a%a%a?)%-%a%a$" )
                script = ISO15924.getLanguageScript( script )
            end
        end
        if script then
            script = script:sub( 1, 1 ):upper() ..
                     script:sub( 2 ):lower()
            r = got[ script ]
        end
    end
    return r or false
end -- fulfil()



ISO15924.Text.scriptName = function ( assigned, alien, add )
    -- Retrieve script name, hopefully linked
    -- Precondition:
    --     assigned  -- string, with script code
    --     alien     -- string, with language code, or not
    --     add       -- arbitrary additional information
    -- Returns string
    local r, trsl
    if type( assigned ) == "string"  and
       assigned:match( "^%u%l%l%l$" ) then
        trsl = ISO15924.fetch( "translate" )
        r    = assigned
    else
        r = ""
    end
    if type( trsl ) == "table" then
        local slang
        if type( alien ) == "string"  and
           alien:match( "^%l%l%l?%-?" ) then
            slang = alien:lower()
        end
        if not slang then
            if not ISO15924.Text.sublang then
                local title = mw.title.getCurrentTitle()
                ISO15924.Text.sublang = title.text:match( "/%l%l%l?$" )
                ISO15924.Text.sublang = ISO15924.Text.sublang or true
            end
            if type( ISO15924.Text.sublang ) == "string"  and
               type( trsl[ ISO15924.Text.sublang ] ) == "table" then
                slang = ISO15924.Text.sublang
            end
        end
        if not slang then
            if not ISO15924.Text.sitelang then
                local contLang = mw.language.getContentLanguage()
                ISO15924.Text.sitelang = contLang:getCode():lower()
            end
            slang = ISO15924.Text.sitelang
        end
        if type( trsl[ slang ] ) == "table" then
            trsl = trsl[ slang ]
        elseif type( trsl.en ) == "table" then
            trsl  = trsl.en
            slang = "en"
        else
            trsl = false
        end
        if trsl then
            local pages = ISO15924.fetch( "pages" )
            trsl = trsl[ assigned ]
            if type( trsl ) == "string" then
                r = trsl
            elseif type( trsl ) == "table" then
                if type( trsl[ 1 ] ) == "string" then
                    r = trsl[ 1 ]
                    if add  and  slang == "de" then
                        if tonumber( add ) == 2  and
                           type( trsl[ 2 ] ) == "string" then
                            r = trsl[ 2 ]
                        end
                    end
                end
            end
            if type( pages ) == "table" then
                local p
                for k, v in pairs( pages ) do
                    if type( v ) == "table"  and  v.lang == slang then
                        p = v
                        break    -- for k, v
                    end
                end -- for k, v
                if p  and  type( p.targets ) == "table" then
                    p = p.targets[ assigned ]
                    if type( p ) == "string" then
                        -- different server issues --
                        if mw.ustring.upper( mw.ustring.sub( p, 1, 1 ) )
                           ~=
                           mw.ustring.upper( mw.ustring.sub( r, 1, 1 ) )
                           or  mw.ustring.sub( p, 2 ) ~=
                               mw.ustring.sub( r, 2 ) then
                            r = string.format( "%s|%s", p, r )
                        end
                        r = string.format( "[[%s]]", r )
                    end
                end
            end
            if add  and  slang == "de" then
                if tonumber( add ) == 2 then
                    local s = "in "
                    if type( trsl ) == "table" and
                       type( trsl[ 3 ] ) == "string" then
                        s = trsl[ 3 ] .. " "
                    end
                    r = s .. r
                end
            end
        end
    end
    return r
end -- ISO15924.Text.scriptName()



Unicode.flat = function ( analyse )
    -- Remove markup and syntax from wikitext
    -- Precondition:
    --     analyse  -- string, with wikitext
    -- Returns string, with cleaned content plain text
    local r = analyse
    if r:find( "&", 1, true ) then
        r = mw.text.decode( r, true )
    end
    r = mw.text.trim( mw.text.unstrip( r ) )
    if r:find( "<", 1, true )  and
       r:find( ">", 1, true ) then
        r = r:gsub( "(</?%l[^>]*>)", "" )
    end
    if r:find( "[", 1, true )    and
       ( ( r:find( "[[", 1, true )  and
           r:find( "]]", 1, true ) )   or
         r:find( "[http", 1, true )   or
         r:find( "[//", 1, true ) ) then
        local lucky, WLink = pcall( require, "Module:WLink" )
        if type( WLink ) == "table" then
            r = WLink.WLink().getPlain( r )
        end
    end
    return r
end -- Unicode.flat()



Unicode.getRanges = function ()
    -- Retrieve collection of Unicode ranges
    -- Returns table, with all relations codepoint / scripts
    if type( Unicode.ranges ) ~= "table" then
        local e, unique
        Unicode.ranges = { }
        unique = ISO15924.fetch( "reverse" )
        for k, range in pairs( unique ) do
            e = { }
            for j, v in pairs( range ) do
                table.insert( e, v )
            end -- for j, v
            table.insert( Unicode.ranges, e )
        end -- for k, range
    end
    return Unicode.ranges
end -- Unicode.getRanges()



Unicode.getScripts = function ( allow, analyse, assume )
    -- Check all chars for expected script code ranges
    -- Precondition:
    --     allow    -- table, with permitted unspecific ranges
    --     analyse  -- string or number or table, with text
    --     assume   -- string, or nil, with ID of expected script
    -- Returns table, with all relations codepoint / scripts
    local uc = Unicode.getRanges()
    local cp = type( analyse )
    local r  = { }
    local e, n, p, s, v
    if cp == "string" then
        e  = Unicode.flat( analyse )
        cp = { }
        n  = mw.ustring.len( e )
        for i = 1, n do
            table.insert( cp,  mw.ustring.codepoint( e, i, i ) )
        end -- for i
    elseif cp == "table" then
        cp = analyse
    elseif cp == "number" then
        cp = { analyse }
    end
    for i = 1, #cp do
        n = cp[ i ]
        p = { n, false }
        for k = 1, #uc do
            e = uc[ k ]
            if n <= e[ 2 ] then
                if n >= e[ 1 ] then
                    v = e[ 3 ]
                    if type( v ) == "table" then
                        s = v[ 1 ]
                        if assume then
                            for j = 2, #v do
                                if v[ j ] == assume then
                                    s = v[ j ]
                                    break -- for j
                                end
                            end -- for j
                        end
                    else
                        s = "???"
                    end
                    p[ 2 ] = s
                    n = false
                end
                break -- for k
            elseif n < e[ 1 ] then
                break -- for k
            end
        end -- for k
        if n then
            for j = 1, #allow do
                e = allow[ j ]
                if n <= e[ 2 ] then
                    if n >= e[ 1 ] then
                        p[ 2 ] = true
                    end
                    break -- for j
                elseif n < e[ 1 ] then
                    break -- for j
                end
            end -- for j
        end
        table.insert( r, p )
    end -- for i
    return r
end -- Unicode.getScripts()



Unicode.isScript = function ( all, ask, analyse )
    -- Check all chars for expected script code ranges
    -- Precondition:
    --     all      -- table, with all definitions
    --     ask      -- string, with supposed script code
    --     analyse  -- string or number or table, with text
    -- Returns
    --     1. true, if all chars within
    --     2. table, with analyse text
    local f = function ( array, amount, a )
                  local k = a
                  local e
                  for i = 1, amount do
                      e = array[ i ]
                      if k >= e[ 1 ] then
                          if k <= e[ 2 ] then
                              k = false
                              break -- for i
                          end
                      else
                          break -- for i
                      end
                  end -- for i
                  return k
              end
    local s  = analyse
    local cp = type( s )
    local uc = { }
    local xx = { }
    local r  = true
    local m, na, nu, nx
    if cp == "string" then
        s  =  Unicode.flat( s )
        cp = { }
        na = mw.ustring.len( s )
        for i = 1, na do
            table.insert( cp,  mw.ustring.codepoint( s, i, i ) )
        end -- for i
    elseif cp == "table" then
        cp = s
    elseif cp == "number" then
        cp = { s }
    else
        cp = { }
    end
    Unicode.merge( uc, all, ask )
    Unicode.merge( xx, all, "*" )
    na = #cp
    nu = #uc
    nx = #xx
    for j = 1, na do
        m = f( uc, nu, cp[ j ] )
        if m then
            m = f( xx, nx, m )
            if m then
                r = false
                break -- for j
            end
        end
    end -- for j
    return r, cp
end -- Unicode.isScript()



Unicode.merge = function ( accumulate, all, ask, append )
    -- Ensure single list of items
    -- Precondition:
    --     accumulate  -- table, with collection to be extended
    --     all         -- table, with all definitions
    --     ask         -- string, with requested script code
    --     append      -- true, if code names to be appended to entries
    -- The accumulate table may have been extended
    local g = all[ ask ]
    if type( g ) == "table" then
        local codes, s
        for k, v in pairs( g ) do
            s = type( v )
            break    -- for k, v
        end -- for k, v
        if s == "string" then
            for k, v in pairs( g ) do
                if append then
                    codes = { ask, v }
                    table.sort( codes )
                end
                fill( accumulate, all[ v ], codes )
            end -- for k, v
            Unicode.sort( accumulate )
        elseif s == "table" then
            if append then
                codes = { ask }
            end
            fill( accumulate, g, codes )
        end
    end
end -- Unicode.merge()



Unicode.romanNumbers = function ( array, at )
    -- Check for possible roman numbers
    -- Precondition:
    --     array  -- table, with elements as sequence tables
    --     all    -- number, with position within array
    -- Returns number, which is identical or greater than at, to proceed
    local r = at
    local e = array[ r ]
    if Unicode.RomanN.dig[ e[ 1 ] ]  and
       r > 1  and
       Unicode.RomanN.bef[ array[ r - 1 ][ 1 ] ] then
        local j = r
        while j < #array do
            e = array[ j + 1 ]
            if Unicode.RomanN.dig[ e[ 1 ] ] then
                j = j + 1
            else
                break    -- while j
            end
        end    -- while j
        if j == #array  or
           Unicode.RomanN.fol[ e[ 1 ] ] then
            r = j + 1
        end
    end
    return r
end -- Unicode.romanNumbers()



Unicode.showScripts = function ( analysed )
    -- Retrieve codepoints and assigned script codes for string
    -- Precondition:
    --     analysed  -- table, as returned by Unicode.getScripts()
    -- Returns string, with every codepoint-script identified
    local r = ""
    local c, d, k, s
    for i = 1, #analysed do
        c = analysed[ i ]
        k = c[ 1 ]
        s = string.format( "%X", k )
        d = c[ 2 ]
        if d then
            if type( d ) == "string" then
                s = string.format( "%s-%s-%s",
                                   s,
                                   mw.ustring.char( k ),
                                   d )
            end
        else
            s = s .. "-????"
        end
        r = string.format( "%s %s", r, s )
    end -- for i
    return r
end -- Unicode.showScripts()



Unicode.sort = function ( apply )
    -- Sort code ranges
    --     apply  -- table, with request
    local function f( a1, a2 )
              return a1[ 1 ] < a2[ 1 ]
          end
    table.sort( apply, f )
end -- Unicode.sort()



Unicode.testScripts = function ( assume, analyse )
    -- Check whether all chars match script
    -- Precondition:
    --     assume   -- string, with expected script code
    --     analyse  -- string or number or table, with text
    -- Postcondition:
    --     Returns
    --         1. number, of chars matching assume
    --         2. number, of chars violating assume
    local rA = 0
    local rX = 0
    local xx = { }
    local i  = 1
    local cp, e, p
    Unicode.merge( xx, ISO15924.fetch( "unicodes" ), "*" )
    cp = Unicode.getScripts( xx, analyse, assume )
    while i <= #cp do
        e = cp[ i ]
        p = e[ 2 ]
        if type( p ) == "string" then
            if p == assume then
                rA = rA + 1
            elseif p == "Latn" then
                local j = Unicode.romanNumbers( cp, i )
                if j > i then
                    i = j
                    rX = rX - 1
                end
                rX = rX + 1
            end
        end
        i = i + 1
    end    -- while i
    return rA, rX
end -- Unicode.testScripts()



ISO15924.fetch = function ( access, alert )
    -- Fetch mw.loadData component
    -- Precondition:
    --     access  -- table name
    --     alert   -- true, for throwing error on data problem
    -- Postcondition:
    --     Returns table
    local r = ISO15924[ access ]
    if type( r ) ~= "table" then
        local ext, s, sub
        if not ISO15924.config then
            ISO15924.config = true
            ISO15924.fetch( "config", alert )    -- self
            if ISO15924.config.live then
                ISO15924.statics = "commons"
            end
        end
        for i = 1, #ISO15924.Commons do
            s = ISO15924.Commons[ i ]
            if s == access then
                sub = ISO15924.statics
                break -- for i
            end
        end -- for i
        sub = sub or access
        ISO15924.loadData = ISO15924.loadData or { }
        if ISO15924.loadData[ sub ] then
            ext = ISO15924.loadData[ sub ]
        else
            ext = foreignModule( ISO15924.suite,
                                 false,
                                 sub,
                                 ISO15924.item,
                                 alert )
            ISO15924.loadData[ sub ] = ext
        end
        if type( ext ) == "table" then
            if type( ext[ access ] ) == "table" then
               r = ext[ access ]
            elseif sub == "config" then
                r = ext
            else
                r = { }
            end
        else
            r = { }
        end
        ISO15924[ access ] = r
    end
    return r
end -- ISO15924.fetch()



ISO15924.getLanguageScript = function ( ask )
    -- Retrieve primary script for language
    -- Precondition:
    --     ask  -- string, with language code
    -- Returns string, with associated script code
    local r
    if type( ask ) == "string" then
        local s = ask
        local n = #s
        if n == 7  or  n == 8 then
            r = s:match( "^%a%a%a?%-(%a%a%a%a)$" )
            if r then
                r = r:sub( 1, 1 ):upper() ..
                    r:sub( 2 ):lower()
            end
        elseif n > 3 then
            s = s:match( "^(%a%a%a?)%-" )
        end
        if not r and s then
            local written = ISO15924.fetch( "iso639script" )
            if type( written ) == "table" then
                r = written[ s:lower() ]
                if type( r ) == "table" then
                    r = r[ 1 ]
                end
            end
        end
    end
    return r or "Latn"
end -- ISO15924.getLanguageScript()



ISO15924.getScripts = function ( analyse )
    -- Retrieve codepoints and assigned script codes
    -- Precondition:
    --     analyse  -- string or number or table, with text
    -- Returns table, with all relations codepoint / scripts
    local xx = { }
    Unicode.merge( xx,  ISO15924.fetch( "unicodes" ),  "*" )
    return Unicode.getScripts( xx, analyse, false )
end -- ISO15924.getScripts()



ISO15924.isCJK = function ( ask )
    -- Check whether script is Chinese-Japanese-Korean (CJK)
    -- Precondition:
    --     ask  -- string, with language or script code
    -- Returns true, if CJK
    return fulfil( ask, "cjk" )
end -- ISO15924.isCJK()



ISO15924.isRTL = function ( ask )
    -- Check whether script is right-to-left
    -- Precondition:
    --     ask  -- string, with language or script code
    -- Returns true, if right-to-left
    return fulfil( ask, "rtl" )
end -- ISO15924.isRTL()



ISO15924.isScript = function ( assume, analyse )
    -- Check all chars for expected script code ranges
    -- Precondition:
    --     assume   -- string, with expected script code
    --     analyse  -- string or number or table, with text
    -- Returns
    --     1. true, if all chars within
    --     2. analyse as table
    return Unicode.isScript( ISO15924.fetch( "unicodes" ),
                             assume,
                             analyse )
end -- ISO15924.isScript()



ISO15924.isTrans = function ( ask, assign, about )
    -- Check whether valid transcription for context
    -- Precondition:
    --     ask     -- string, with transcription key
    --     assign  -- string, with language or scripting code
    --     about   -- string or nil, with site scripting code
    -- Postcondition:
    --     Returns boolean
    local r = false
    local t, trans
    local r, trsl
    if type( ask ) == "string" then
        local trans = ISO15924.fetch( "trans" )
        local t = trans[ assign ]
        if type( t ) == "table" then
            for k, v in pairs( t ) do
                if v == ask then
                    r = true
                    break    -- for i
                end
            end -- for k, v
        end
    end
    if not r  and  about == "Latn" then
        r = ( ask == "BGN-PCGN"  or  ask == "ALA-LC" )
    end
    return r
end -- ISO15924.isTrans()



ISO15924.scriptName = function ( assigned, alien, add )
    -- Retrieve script name, hopefully linked
    -- Precondition:
    --     assigned  -- string, with script code
    --     alien     -- string, with language code, or not
    --     add       -- arbitrary additional information
    -- Returns string
    return ISO15924.Text.scriptName( assigned, alien, add )
end -- ISO15924.scriptName()



ISO15924.showScript = function ( analyse )
    -- Retrieve assigned script code of first character
    -- Precondition:
    --     analyse  -- string or number or table, with text
    -- Returns string, with every codepoint-script identified
    local xx = { }
    local cp, r
    Unicode.merge( xx, ISO15924.fetch( "unicodes" ), "*" )
    cp = Unicode.getScripts( xx, analyse, false )
    if #cp > 0 then
        local s = cp[ 1 ][ 2 ]
        if type( s ) == "string" then
            r = s
        end
    end
    return r or false
end -- ISO15924.showScript()



ISO15924.showScripts = function ( analyse )
    -- Retrieve codepoints and assigned script codes for and as string
    -- Precondition:
    --     analyse  -- string or number or table, with text
    -- Returns string, with every codepoint-script identified
    local xx = { }
    local cp
    Unicode.merge( xx, ISO15924.fetch( "unicodes" ), "*" )
    cp = Unicode.getScripts( xx, analyse, false )
    return Unicode.showScripts( cp )
end -- ISO15924.showScripts()



ISO15924.testScripts = function ( assume, analyse )
    -- Check whether all chars match script
    -- Precondition:
    --     assume   -- string, with expected script code
    --     analyse  -- string or number or table, with text
    -- Postcondition:
    --     Returns
    --         1. number, of chars matching assume
    --         2. number, of chars violating assume
    return Unicode.testScripts( assume, analyse )
end -- ISO15924.testScripts()



Failsafe.failsafe = function ( atleast )
    -- Retrieve versioning and check for compliance
    -- Precondition:
    --     atleast  -- string, with required version or "wikidata" or "~"
    --                 or false
    -- Postcondition:
    --     Returns  string  -- with queried version, also if problem
    --              false   -- if appropriate
    -- 2019-10-15
    local last  = ( atleast == "~" )
    local since = atleast
    local r
    if last  or  since == "wikidata" then
        local item = Failsafe.item
        since = false
        if type( item ) == "number"  and  item > 0 then
            local entity = mw.wikibase.getEntity( string.format( "Q%d",
                                                                 item ) )
            if type( entity ) == "table" then
                local seek = Failsafe.serialProperty or "P348"
                local vsn  = entity:formatPropertyValues( seek )
                if type( vsn ) == "table"  and
                   type( vsn.value ) == "string"  and
                   vsn.value ~= "" then
                    if last  and  vsn.value == Failsafe.serial then
                        r = false
                    else
                        r = vsn.value
                    end
                end
            end
        end
    end
    if type( r ) == "nil" then
        if not since  or  since <= Failsafe.serial then
            r = Failsafe.serial
        else
            r = false
        end
    end
    return r
end -- Failsafe.failsafe()



-- Export
local p = { }

p.getLanguageScript = function ( frame )
    local s = mw.text.trim( frame.args[ 1 ]  or  "" )
    return ISO15924.getLanguageScript( s )
end -- p.getLanguageScript

p.isCJK = function ( frame )
    local s = mw.text.trim( frame.args[ 1 ]  or  "" )
    return ISO15924.isCJK( s )  and  "1"   or   ""
end -- p.isCJK()

p.isRTL = function ( frame )
    local s = mw.text.trim( frame.args[ 1 ]  or  "" )
    return ISO15924.isRTL( s )  and  "1"   or   ""
end -- p.isRTL()

p.isScript = function ( frame )
    local s1 = mw.text.trim( frame.args[ 1 ]  or  "" )
    local s2 = mw.text.trim( frame.args[ 2 ]  or  "" )
    local r, cp = ISO15924.isScript( s1, s2 )
    return r and "1"  or  ""
end -- p.isScript

p.isTrans = function ( frame )
    -- Check whether valid transcription for context
    --     1     -- string, with transcription key
    --     2     -- string, with language or scripting code
    --     site  -- string or nil, with site scripting code
    local s1   = mw.text.trim( frame.args[ 1 ]  or  "" )
    local s2   = mw.text.trim( frame.args[ 2 ]  or  "" )
    local site = mw.text.trim( frame.args.site  or  "" )
    return ISO15924.isTrans( s1, s2, site )  and  "1"   or   ""
end -- p.isTrans

p.scriptName = function ( frame )
    local s1    = mw.text.trim( frame.args[ 1 ]  or  "" )
    local s2    = mw.text.trim( frame.args[ 2 ]  or  "" )
    local slang = mw.text.trim( frame.args.lang  or  "" )
    return ISO15924.Text.scriptName( s1, slang, s2 )
end -- p.scriptName

p.showScript = function ( frame )
    local s = frame.args[ 1 ]
    local r
    if s then
        s = mw.text.trim( s )
        if s ~= "" then
            if s:sub( 1, 2 ) == "U+" then
                s = s:match( "^U%+(%x+)$" )
                if s then
                    s = tonumber( s, 16 )
                end
            end
            if s then
                r = ISO15924.showScript( s )
            end
        end
    end
    return r or ""
end -- p.showScript

p.showScripts = function ( frame )
    local s = frame.args[ 1 ]
    local r
    if s then
        r = ISO15924.showScripts( mw.text.trim( s ) )
    else
        r = ""
    end
    return r
end -- p.showScripts

p.failsafe = function ( frame )
    -- Versioning interface
    local s = type( frame )
    local since
    if s == "table" then
        since = frame.args[ 1 ]
    elseif s == "string" then
        since = frame
    end
    if since then
        since = mw.text.trim( since )
        if since == "" then
            since = false
        end
    end
    return Failsafe.failsafe( since )  or  ""
end -- p.failsafe()

p.ISO15924 = function ()
    return ISO15924
end -- p.ISO15924

return p