fix some regressions

- some compilation error
- STDERR seems not to work in Crystal 0.7.2

crisp.cr

@@ -4,7 +4,7 @@ if ARGV.empty?
   begin
     Crisp::Interpreter.new.run
   rescue e
-    o">STDERR.puts e
+    b">puts e
     exit 1
   end
 else

src/crisp/interpreter.cr

@@ -15,9 +15,10 @@ module Crisp
 
   class Interpreter
     def initialize(args = nil)
+      @printer = Printer.new
       @env = Crisp::Env.new
 
-      Crisp::NameSpace.each{|k,v| @curent_env.set(k, Crisp::Type.new(v))}
+      Crisp::NameSpace.each{|k,v| @env.set(k, Crisp::Type.new(v))}
       @env.set("eval", Crisp::Type.new -> (args: Array(Crisp::Type)){ eval(args[0], @env) })
 
       eval_string "(def! not (fn* (a) (if a false true)))"
@@ -35,8 +36,6 @@ module Crisp
       end
 
       @env.set("*ARGV*", Crisp::Type.new argv)
-
-      @printer = Printer.new
     end
 
     def func_of(env, binds, body)
@@ -72,7 +71,7 @@ module Crisp
     end
 
     def read(str)
-      read_str str
+      Crisp.read_str str
     end
 
     macro pair?(list)
@@ -278,7 +277,7 @@ module Crisp
         begin
           puts eval_string(line)
         rescue e
-          o">STDERR.puts e
+          b">puts e.message
         end
       end
     end

src/crisp/types.cr

@@ -1,6 +1,8 @@
 require "./printer"
 
 module Crisp
+  extend self
+
   class Symbol
     property :str
     def initialize(@str)
@@ -100,10 +102,10 @@ module Crisp
   end
 
   alias Func = Type::Func
+end
 
-  macro gen_type(t, *args)
-    Crisp::Type.new {{t.id}}.new({{*args}})
-  end
+macro gen_type(t, *args)
+  Crisp::Type.new {{t.id}}.new({{*args}})
 end
 
 class Array