lua/types.lua

   1 local utils = require('utils')
   2
   3 local M = {}
   4
   5 -- type functions
   6
   7 function M._sequential_Q(obj)
   8     return M._list_Q(obj) or M._vector_Q(obj)
   9 end
  10
  11 function M._equal_Q(a,b)
  12     if M._symbol_Q(a) and M._symbol_Q(b) then
  13         return a.val == b.val
  14     elseif M._sequential_Q(a) and M._sequential_Q(b) then
  15         if #a ~= #b then return false end
  16         for i, v in ipairs(a) do
  17             if not M._equal_Q(v,b[i]) then return false end
  18         end
  19         return true
  20     elseif M._hash_map_Q(a) and M._hash_map_Q(b) then
  21         if #a ~= #b then return false end
  22         for k, v in pairs(a) do
  23             if not M._equal_Q(v,b[k]) then return false end
  24         end
  25         return true
  26     else
  27         return a == b
  28     end
  29 end
  30
  31 function M.copy(obj)
  32     if type(obj) == "function" then
  33         return M.FunctionRef:new(obj)
  34     end
  35     if type(obj) ~= "table" then return obj end
  36
  37     -- copy object data
  38     local new_obj = {}
  39     for k,v in pairs(obj) do
  40         new_obj[k] = v
  41     end
  42
  43     -- copy metatable and link to original
  44     local old_mt = getmetatable(obj)
  45     if old_mt ~= nil then
  46         local new_mt = {}
  47         for k,v in pairs(old_mt) do
  48             new_mt[k] = v
  49         end
  50         setmetatable(new_mt, old_mt)
  51         setmetatable(new_obj, new_mt)
  52     end
  53
  54     return new_obj
  55 end
  56
  57 function M.slice(lst, start, last)
  58     if last == nil then last = #lst end
  59     local new_lst = {}
  60     if start <= last then
  61         for i = start, last do
  62             new_lst[#new_lst+1] = lst[i]
  63         end
  64     end
  65     return new_lst
  66 end
  67
  68 -- Error/exceptions
  69
  70 M.MalException = {}
  71 function M.MalException:new(val)
  72     local newObj = {val = val}
  73     self.__index = self
  74     return setmetatable(newObj, self)
  75 end
  76 function M._malexception_Q(obj)
  77     return utils.instanceOf(obj, M.MalException)
  78 end
  79
  80 function M.throw(val)
  81     error(M.MalException:new(val))
  82 end
  83
  84 -- Nil
  85
  86 local NilType = {}
  87 function NilType:new(val)
  88     local newObj = {}
  89     self.__index = self
  90     return setmetatable(newObj, self)
  91 end
  92 M.Nil = NilType:new()
  93 function M._nil_Q(obj)
  94     return obj == Nil
  95 end
  96
  97 -- Strings
  98 function M._string_Q(obj)
  99     return type(obj) == "string"
 100 end
 101
 102 -- Symbols
 103
 104 M.Symbol = {}
 105 function M.Symbol:new(val)
 106     local newObj = {val = val}
 107     self.__index = self
 108     return setmetatable(newObj, self)
 109 end
 110 function M._symbol_Q(obj)
 111     return utils.instanceOf(obj, M.Symbol)
 112 end
 113
 114 -- Keywords
 115 function M._keyword_Q(obj)
 116     return M._string_Q(obj) and "\177" == string.sub(obj,1,1)
 117 end
 118
 119
 120 -- Lists
 121
 122 M.List = {}
 123 function M.List:new(lst)
 124     local newObj = lst and lst or {}
 125     self.__index = self
 126     return setmetatable(newObj, self)
 127 end
 128 function M._list_Q(obj)
 129     return utils.instanceOf(obj, M.List)
 130 end
 131 function M.List:slice(start,last)
 132     return M.List:new(M.slice(self,start,last))
 133 end
 134
 135 -- Vectors
 136
 137 M.Vector = {}
 138 function M.Vector:new(lst)
 139     local newObj = lst and lst or {}
 140     self.__index = self
 141     return setmetatable(newObj, self)
 142 end
 143 function M._vector_Q(obj)
 144     return utils.instanceOf(obj, M.Vector)
 145 end
 146 function M.Vector:slice(start,last)
 147     return M.Vector:new(M.slice(self,start,last))
 148 end
 149
 150 -- Hash Maps
 151 --
 152 M.HashMap = {}
 153 function M.HashMap:new(val)
 154     local newObj = val and val or {}
 155     self.__index = self
 156     return setmetatable(newObj, self)
 157 end
 158 function M.hash_map(...)
 159     return M._assoc_BANG(M.HashMap:new(), unpack(arg))
 160 end
 161 function M._hash_map_Q(obj)
 162     return utils.instanceOf(obj, M.HashMap)
 163 end
 164 function M._assoc_BANG(hm, ...)
 165     for i = 1, #arg, 2 do
 166         hm[arg[i]] = arg[i+1]
 167     end
 168     return hm
 169 end
 170 function M._dissoc_BANG(hm, ...)
 171     for i = 1, #arg do
 172         hm[arg[i]] = nil
 173     end
 174     return hm
 175 end
 176
 177 -- Functions
 178
 179 M.MalFunc = {}
 180 function M.MalFunc:new(fn, ast, env, params)
 181     local newObj = {fn = fn, ast = ast, env = env,
 182                     params = params, ismacro = false}
 183     self.__index = self
 184     return setmetatable(newObj, self)
 185 end
 186 function M._malfunc_Q(obj)
 187     return utils.instanceOf(obj, M.MalFunc)
 188 end
 189
 190 -- Atoms
 191
 192 M.Atom = {}
 193 function M.Atom:new(val)
 194     local newObj = {val = val}
 195     self.__index = self
 196     return setmetatable(newObj, self)
 197 end
 198 function M._atom_Q(obj)
 199     return utils.instanceOf(obj, M.Atom)
 200 end
 201
 202 -- FunctionRefs
 203
 204 M.FunctionRef = {}
 205 function M.FunctionRef:new(fn)
 206     local newObj = {fn = fn}
 207     return setmetatable(newObj, self)
 208 end
 209 function M._functionref_Q(obj)
 210     return utils.instanceOf(obj, M.FunctionRef)
 211 end
 212 function M.FunctionRef:__call(...)
 213     return self.fn(...)
 214 end
 215
 216 return M