lua/env.lua

   1 local rex = require('rex_pcre')
   2 local string = require('string')
   3 local table = require('table')
   4 local utils = require('utils')
   5 local types = require('types')
   6
   7 local Env = {}
   8
   9 function Env:new(outer, binds, exprs)
  10     local data = {}
  11     local newObj = {outer = outer, data = data}
  12     self.__index = self
  13     if binds then
  14         for i, b in ipairs(binds) do
  15             if binds[i].val == '&' then
  16                 local new_exprs = types.List:new()
  17                 for j = i, #exprs do
  18                     table.insert(new_exprs, exprs[j])
  19                 end
  20                 table.remove(exprs, 1)
  21                 data[binds[i+1].val] = new_exprs
  22                 break
  23             end
  24             data[binds[i].val] = exprs[i]
  25         end
  26     end
  27     return setmetatable(newObj, self)
  28 end
  29 function Env:find(sym)
  30     if self.data[sym.val] ~= nil then
  31         return self
  32     else
  33         if self.outer ~= nil then
  34             return self.outer:find(sym)
  35         else
  36             return nil
  37         end
  38     end
  39 end
  40 function Env:set(sym,val)
  41     self.data[sym.val] = val
  42     return val
  43 end
  44 function Env:get(sym)
  45     local env = self:find(sym)
  46     if env then
  47         return env.data[sym.val]
  48     else
  49         types.throw("'"..sym.val.."' not found")
  50     end
  51 end
  52
  53 return Env