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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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