View difference between Paste ID: ZsE9BvQM and H3gPsEeC

 local json = {}
 do
 
   local valuePipes = {}
 
-  local function pipeValue(json, copyPos, pos)
+  local function pipeValue(jsonStr, copyPos, pos)
-    local cPos, c = json:match('()(%S)', pos)
+    local cPos, c = jsonStr:match('()(%S)', pos)
     if not c then
       error('unexpected end of input')
     end
     local pipe = valuePipes[c]
     if not pipe then
       error('invalid JSON at: ' .. cPos)
     end
-    return pipe(json, copyPos, cPos)
+    return pipe(jsonStr, copyPos, cPos)
   end
 
-  function json.parse(json)
+  function json.parse(jsonStr)
     local chunk = assert(load(coroutine.wrap(function()
-      coroutine.yield('return ')
+      coroutine.yield('local json = ...; return ')
-      local copyPos, pos = pipeValue(json, 1, 1)
+      local copyPos, pos = pipeValue(jsonStr, 1, 1)
-      local invalidPos = json:match('()%S', pos)
+      local invalidPos = jsonStr:match('()%S', pos)
       if invalidPos then
         error('invalid JSON at: ' .. invalidPos)
       end
       if (copyPos < pos) then
-        coroutine.yield(json:sub(copyPos))
+        coroutine.yield(jsonStr:sub(copyPos))
       end
     end)))
-    return chunk()
+    return chunk(json)
   end
 
-  local function pipeStringContent(json, copyPos, pos)
+  local function pipeStringContent(jsonStr, copyPos, pos)
     while true do
-      local cPos, c = json:match('()(["\\])', pos)
+      local cPos, c = jsonStr:match('()(["\\])', pos)
       if (c == '"') then
         return copyPos, cPos+1
       elseif (c == '\\') then
-        local escape = json:sub(cPos+1, cPos+1)
+        local escape = jsonStr:sub(cPos+1, cPos+1)
         if (escape == 'u') then
-          local code = tonumber(json:sub(cPos+2, cPos+5), 16)
+          local code = tonumber(jsonStr:sub(cPos+2, cPos+5), 16)
           if not code then
             error('invalid string escape')
           end
           if (code < 0x80) then
             code = string.format('\\%03d', code)
           elseif (code < 0x800) then
             code = string.format('\\%03d\\%03d',
               0xC0 + math.floor(code/0x40),
               0x80 + code%0x40)
           else
             code = string.format('\\%03d\\%03d\\%03d',
               0xE0 + math.floor(code/0x1000),
               0x80 + math.floor(code/0x40)%0x40,
               0x80 + code%0x40)
           end
-          coroutine.yield(json:sub(copyPos, cPos-1) .. code)
+          coroutine.yield(jsonStr:sub(copyPos, cPos-1) .. code)
           copyPos = cPos+6
           pos = copyPos
         elseif escape == '/' then
-          coroutine.yield(json:sub(copyPos, cPos-1) .. '/')
+          coroutine.yield(jsonStr:sub(copyPos, cPos-1) .. '/')
           pos = cPos+2
           copyPos = pos
         elseif escape:match('["\\bfnrt]') then
           pos = cPos+2
         else
           error('invalid string escape')
         end
       else
         error('unexpected end of input')
       end
     end
   end
 
-  valuePipes['['] = function(json, copyPos, pos)
+  valuePipes['['] = function(jsonStr, copyPos, pos)
-    coroutine.yield(json:sub(copyPos, pos-1) .. 'json.array{')
+    coroutine.yield(jsonStr:sub(copyPos, pos-1) .. 'json.array{')
     copyPos = pos+1
     pos = copyPos
-    local emptyPos = json:match('^%s*%]()', copyPos)
+    local emptyPos = jsonStr:match('^%s*%]()', copyPos)
     if emptyPos then
       coroutine.yield('}')
       return emptyPos, emptyPos
     end
     while true do
-      copyPos, pos = pipeValue(json, copyPos, pos)
+      copyPos, pos = pipeValue(jsonStr, copyPos, pos)
-      local cPos, c = json:match('()(%S)', pos)
+      local cPos, c = jsonStr:match('()(%S)', pos)
       if not c then
         error('unexpected end of input')
       end
       if (c == ']') then
-        coroutine.yield(json:sub(copyPos, cPos-1) .. '}')
+        coroutine.yield(jsonStr:sub(copyPos, cPos-1) .. '}')
         return cPos+1, cPos+1
       elseif (c ~= ',') then
         error('invalid JSON at: ' .. cPos)
       end
       pos = cPos+1
     end
   end
-  valuePipes['"'] = function(json, copyPos, pos)
+  valuePipes['"'] = function(jsonStr, copyPos, pos)
-    return pipeStringContent(json, copyPos, pos+1)
+    return pipeStringContent(jsonStr, copyPos, pos+1)
   end
-  valuePipes['{'] = function(json, copyPos, pos)
+  valuePipes['{'] = function(jsonStr, copyPos, pos)
     pos = pos + 1
-    local emptyPos = json:match('^%s*%}()', pos)
+    local emptyPos = jsonStr:match('^%s*%}()', pos)
     if emptyPos then
       return copyPos, emptyPos
     end
     while true do
-      local keyPos, key = json:match('^%s*()(%S)', pos)
+      local keyPos, key = jsonStr:match('^%s*()(%S)', pos)
       if (key ~= '"') then
         if not keyPos then
           error('unexpected end of input')
         end
         error('invalid JSON at: ' .. pos)
       end
-      coroutine.yield(json:sub(copyPos, keyPos-1) .. '["')
+      coroutine.yield(jsonStr:sub(copyPos, keyPos-1) .. '["')
-      copyPos, pos = pipeStringContent(json, keyPos+1, keyPos+1)
+      copyPos, pos = pipeStringContent(jsonStr, keyPos+1, keyPos+1)
-      local valPos, v = json:match('^%s*()(%S)', pos)
+      local valPos, v = jsonStr:match('^%s*()(%S)', pos)
       if (v ~= ':') then
         if not valPos then
           error('unexpected end of input')
         end
         error('invalid JSON at: ' .. pos)
       end
-      coroutine.yield(json:sub(copyPos, pos-1) .. ']=')
+      coroutine.yield(jsonStr:sub(copyPos, pos-1) .. ']=')
-      copyPos, pos = pipeValue(json, valPos+1, valPos+1)
+      copyPos, pos = pipeValue(jsonStr, valPos+1, valPos+1)
-      local cPos, c = json:match('()(%S)', pos)
+      local cPos, c = jsonStr:match('()(%S)', pos)
       if not c then
         error('unexpected end of input')
       end
       pos = cPos + 1
       if (c == '}') then
         return copyPos, pos
       elseif (c ~= ',') then
         error('invalid JSON at: ' .. cPos)
       end
     end
   end
-  valuePipes['t'] = function(json, copyPos, pos)
+  valuePipes['t'] = function(jsonStr, copyPos, pos)
-    assert(json:sub(pos, pos+3) == 'true', 'invalid JSON at: ' .. pos)
+    assert(jsonStr:sub(pos, pos+3) == 'true', 'invalid JSON at: ' .. pos)
     return copyPos, pos+4
   end
-  valuePipes['f'] = function(json, copyPos, pos)
+  valuePipes['f'] = function(jsonStr, copyPos, pos)
-    assert(json:sub(pos, pos+4) == 'false', 'invalid JSON at: ' .. pos)
+    assert(jsonStr:sub(pos, pos+4) == 'false', 'invalid JSON at: ' .. pos)
     return copyPos, pos+5
   end
-  valuePipes['n'] = function(json, copyPos, pos)
+  valuePipes['n'] = function(jsonStr, copyPos, pos)
-    assert(json:sub(pos, pos+3) == 'null', 'invalid JSON at: ' .. pos)
+    assert(jsonStr:sub(pos, pos+3) == 'null', 'invalid JSON at: ' .. pos)
-    coroutine.yield(json:sub(copyPos, pos-1) .. 'json.')
+    coroutine.yield(jsonStr:sub(copyPos, pos-1) .. 'json.')
     return pos, pos+4
   end
-  local function numParser(json, copyPos, pos)
+  local function numParser(jsonStr, copyPos, pos)
-    local afterPos = json:match('^%-?[0-9]+()', pos)
+    local afterPos = jsonStr:match('^%-?[0-9]+()', pos)
     if not afterPos then
       error('invalid JSON at: ' .. pos)
     end
-    afterPos = json:match('^%.[0-9]+()', afterPos) or afterPos
+    afterPos = jsonStr:match('^%.[0-9]+()', afterPos) or afterPos
-    afterPos = json:match('^[eE][%+%-]?[0-9]+()', afterPos) or afterPos
+    afterPos = jsonStr:match('^[eE][%+%-]?[0-9]+()', afterPos) or afterPos
     return copyPos, afterPos
   end
   for i = 0, 9 do
     valuePipes[tostring(i)] = numParser
   end
   valuePipes['-'] = numParser
 
   -- override to replace default functionality
   json.null = nil
   json.array = function(a)
     return a
   end
 
 end
-return json
+return json