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     else
  21         return a == b
  22     end
  23 end
  24
  25 function M.copy(obj)
  26     if type(obj) == "function" then
  27         return M.FunctionRef:new(obj)
  28     end
  29     if type(obj) ~= "table" then return obj end
  30
  31     -- copy object data
  32     local new_obj = {}
  33     for k,v in pairs(obj) do
  34         new_obj[k] = v
  35     end
  36
  37     -- copy metatable and link to original
  38     local old_mt = getmetatable(obj)
  39     if old_mt ~= nil then
  40         local new_mt = {}
  41         for k,v in pairs(old_mt) do
  42             new_mt[k] = v
  43         end
  44         setmetatable(new_mt, old_mt)
  45         setmetatable(new_obj, new_mt)
  46     end
  47
  48     return new_obj
  49 end
  50
  51 function M.slice(lst, start, last)
  52     if last == nil then last = #lst end
  53     local new_lst = {}
  54     if start <= last then
  55         for i = start, last do
  56             new_lst[#new_lst+1] = lst[i]
  57         end
  58     end
  59     return new_lst
  60 end
  61
  62 -- Error/exceptions
  63
  64 M.MalException = {}
  65 function M.MalException:new(val)
  66     local newObj = {val = val}
  67     self.__index = self
  68     return setmetatable(newObj, self)
  69 end
  70 function M._malexception_Q(obj)
  71     return utils.instanceOf(obj, M.MalException)
  72 end
  73
  74 function M.throw(val)
  75     error(M.MalException:new(val))
  76 end
  77
  78 -- Nil
  79
  80 local NilType = {}
  81 function NilType:new(val)
  82     local newObj = {}
  83     self.__index = self
  84     return setmetatable(newObj, self)
  85 end
  86 M.Nil = NilType:new()
  87 function M._nil_Q(obj)
  88     return obj == Nil
  89 end
  90
  91 -- Strings
  92 function M._string_Q(obj)
  93     return type(obj) == "string"
  94 end
  95
  96 -- Symbols
  97
  98 M.Symbol = {}
  99 function M.Symbol:new(val)
 100     local newObj = {val = val}
 101     self.__index = self
 102     return setmetatable(newObj, self)
 103 end
 104 function M._symbol_Q(obj)
 105     return utils.instanceOf(obj, M.Symbol)
 106 end
 107
 108 -- Keywords
 109 function M._keyword_Q(obj)
 110     return M._string_Q(obj) and "\177" == string.sub(obj,1,1)
 111 end
 112
 113
 114 -- Lists
 115
 116 M.List = {}
 117 function M.List:new(lst)
 118     local newObj = lst and lst or {}
 119     self.__index = self
 120     return setmetatable(newObj, self)
 121 end
 122 function M._list_Q(obj)
 123     return utils.instanceOf(obj, M.List)
 124 end
 125 function M.List:slice(start,last)
 126     return M.List:new(M.slice(self,start,last))
 127 end
 128
 129 -- Vectors
 130
 131 M.Vector = {}
 132 function M.Vector:new(lst)
 133     local newObj = lst and lst or {}
 134     self.__index = self
 135     return setmetatable(newObj, self)
 136 end
 137 function M._vector_Q(obj)
 138     return utils.instanceOf(obj, M.Vector)
 139 end
 140 function M.Vector:slice(start,last)
 141     return M.Vector:new(M.slice(self,start,last))
 142 end
 143
 144 -- Hash Maps
 145 --
 146 M.HashMap = {}
 147 function M.HashMap:new(val)
 148     local newObj = val and val or {}
 149     self.__index = self
 150     return setmetatable(newObj, self)
 151 end
 152 function M.hash_map(...)
 153     return M._assoc_BANG(M.HashMap:new(), unpack(arg))
 154 end
 155 function M._hash_map_Q(obj)
 156     return utils.instanceOf(obj, M.HashMap)
 157 end
 158 function M._assoc_BANG(hm, ...)
 159     for i = 1, #arg, 2 do
 160         hm[arg[i]] = arg[i+1]
 161     end
 162     return hm
 163 end
 164 function M._dissoc_BANG(hm, ...)
 165     for i = 1, #arg do
 166         hm[arg[i]] = nil
 167     end
 168     return hm
 169 end
 170
 171 -- Functions
 172
 173 M.MalFunc = {}
 174 function M.MalFunc:new(fn, ast, env, params)
 175     local newObj = {fn = fn, ast = ast, env = env,
 176                     params = params, ismacro = false}
 177     self.__index = self
 178     return setmetatable(newObj, self)
 179 end
 180 function M._malfunc_Q(obj)
 181     return utils.instanceOf(obj, M.MalFunc)
 182 end
 183
 184 -- Atoms
 185
 186 M.Atom = {}
 187 function M.Atom:new(val)
 188     local newObj = {val = val}
 189     self.__index = self
 190     return setmetatable(newObj, self)
 191 end
 192 function M._atom_Q(obj)
 193     return utils.instanceOf(obj, M.Atom)
 194 end
 195
 196 -- FunctionRefs
 197
 198 M.FunctionRef = {}
 199 function M.FunctionRef:new(fn)
 200     local newObj = {fn = fn}
 201     return setmetatable(newObj, self)
 202 end
 203 function M._functionref_Q(obj)
 204     return utils.instanceOf(obj, M.FunctionRef)
 205 end
 206 function M.FunctionRef:__call(...)
 207     return self.fn(...)
 208 end
 209
 210 return M