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[!] VersionNotice: The below code pertains to an older Lua version, Lua 4. Certain features used like tag methods (settagmethod) are no longer present in Lua 5 but have been replaced with metamethods.

     1

     2  local ENVPAT="%$(%w+)"

     3  local DOTPAT="|((%a%w*)[.:][.:%w]+)|"

     4  local TABPAT="@((%a%w*)[.:%w]*%s*%b{})"

     5  local FUNPAT="@((%a%w*)[.:%w]*%s*%b())"

     6  local ANYPAT="@(%b{})"

     7  local VARPAT="((\n?) *)|(%w+)|"

     8

     9  local sharedvars = {

    10    DATE=date("%d/%m/%Y %T"),

    11  }

    12

    13  function share(t)

    14    for n,v in t do sharedvars[n]=v end

    15  end

    16

    17  local push, pop, join = tinsert, tremove, concat

    18  local getn, call, unpack, globals, rawget, concat, getglobal, gsub, type =

    19        getn, call, unpack, globals, rawget, concat, getglobal, gsub, type

    20

    21  local indent = function( sp, cr, var )

    22    local val = getglobal(var)

    23    if cr and sp ~= cr then val = gsub( val, '\n([^\n])', sp.."%1" ) end

    24    return sp .. val

    25  end

    26

    27  local tagnil = tag(nil)

    28

    29  function fillin( s, pat )

    30    pat = pat or s.template or "*** WARNING: nil pattern ***"

    31    local g  = globals()

    32    s._ERRORMESSAGE = function(x) globals(g) _ERRORMESSAGE(x) end

    33    local tm = gettagmethod( tagnil, 'getglobal' )

    34    settagmethod( tagnil, 'getglobal', function( name, value )

    35        local v

    36        v = s[name] if v then return v end -- support delegation via index

    37        v = sharedvars[name] if v then return v end

    38        v = rawget( g, name ) if v then -- rawget must be local

    39          if type(v) == 'magic' then return v[name]() end

    40          --? local tm = gettagmethod( tag(v), 'getglobal' )

    41          --? if tm then return tm(name,v) end

    42          return v

    43        end

    44        if tm then return tm( name, value ) end

    45        return "*** WARNING: '".. name .."' == nil ***"

    46      end )

    47    globals( s )

    48    local n repeat pat,n = gsub( pat, VARPAT, indent ) until n==0

    49    globals( g )

    50    settagmethod( tagnil, 'getglobal', tm )

    51    return pat

    52  end

    53

    54  local fcnt = 0

    55  local uniq_id = function( x )

    56    fcnt = fcnt + 1

    57    return fcnt .. x

    58  end

    59

    60  function template( pat )

    61    pat = gsub( pat, ENVPAT, getenv )

    62    local mfc = { [[

    63  local Magic = settype( {}, newtype'magic' )

    64  ]] }

    65    local add = function(fc,name)

    66        name = uniq_id(name)

    67        push( mfc, [[

    68  Magic[']].. name ..[['] = function()

    69    local self=globals()

    70    return ]].. fc ..[[ --

    71  end

    72  setglobal(']].. name ..[[', Magic )

    73  ]] )

    74        return '|'.. name ..'|'

    75      end -- add

    76    local doo = function(fc)

    77        local name = uniq_id'ANY'

    78        push( mfc, [[

    79  Magic[']].. name ..[['] = function()

    80    local OUT=''

    81    local self=globals()

    82    do ]].. strsub(fc,2,-2) ..[[ end

    83    return OUT

    84  end

    85  setglobal(']].. name ..[[', Magic )

    86  ]] )

    87        return '|'.. name ..'|'

    88      end -- doo

    89    pat = gsub( pat, DOTPAT, add )

    90    pat = gsub( pat, TABPAT, add )

    91    pat = gsub( pat, FUNPAT, add )

    92    pat = gsub( pat, ANYPAT, doo )

    93  --  write( _STDERR, pat )

    94    local ds = concat( mfc )

    95  --?   ds = ds .. [[

    96  --? settagmethod( tag(Magic), 'getglobal', function( name, magic )

    97  --?     local f = rawget( magic, name )  return f()

    98  --?   end )

    99  --? ]]

   100  --  write( _STDERR, ds )

   101    local _,msg = dostring( ds, 'Make Magic' )

   102    if msg then error( msg .." with\n".. ds ) end

   103    return pat

   104  end

   105

   106

   107  function map( t, fun, ... )

   108    local r = {}

   109    for i = 1, getn(t) do

   110      local v = fun( t[i], unpack(arg) )

   111      push(r,v)

   112    end

   113    return r

   114  end

   115

   116  function grep( t, fun, ... )

   117    local r = {}

   118    for i = 1, getn(t) do

   119      local v = t[i]

   120      if fun( v, unpack(arg) ) then push(r,v) end

   121    end

   122    return r

   123  end

   124

   125  function filleachi( t, sep, pat )

   126    return concat( map( t, fillin, pat ), sep )

   127  end

   128

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