webmcp
view libraries/nihil/nihil.lua @ 2:72860d232f32
Version 1.0.2
Fixed bug with explicit garbage collection (requests > 256kB caused an error)
Views prefixed with an underscore can't be called externally
ui.paginate now displays the last page, if the selected page number is too high.
Fixed bug with explicit garbage collection (requests > 256kB caused an error)
Views prefixed with an underscore can't be called externally
ui.paginate now displays the last page, if the selected page number is too high.
| author | jbe/bsw |
|---|---|
| date | Thu Dec 10 12:00:00 2009 +0100 (2009-12-10) |
| parents | 9fdfb27f8e67 |
| children | 3d43a5cf17c1 |
line source
1 #!/usr/bin/env lua
3 local error = error
4 local getmetatable = getmetatable
5 local module = module
6 local rawset = rawset
7 local setmetatable = setmetatable
9 module(...)
11 metatable = {
12 __tostring = function(self)
13 return "nil" .. self[1]
14 end,
15 __newindex = function()
16 error("Objects representing nil are immutable.")
17 end
18 }
20 nils = setmetatable({}, {
21 __mode = "v",
22 __index = function(self, level)
23 if level > 0 then
24 local result = setmetatable({ level }, metatable)
25 rawset(self, level, result)
26 return result
27 end
28 end,
29 __newindex = function()
30 error("Table is immutable.")
31 end
32 })
34 function lift(value)
35 if value == nil then
36 return nils[1]
37 elseif getmetatable(value) == metatable then
38 return nils[value[1]+1]
39 else
40 return value
41 end
42 end
44 function lower(value)
45 if value == nil then
46 error("Cannot lower nil.")
47 elseif getmetatable(value) == metatable then
48 return nils[value[1]-1]
49 else
50 return value
51 end
52 end