make pr_str() to Crisp::Printer class

src/crisp/core.cr

@@ -42,21 +42,21 @@ module Crisp
     end
   end
 
-  def pr_str_(args)
-    args.map{|a| pr_str(a)}.join(" ")
+  def pr_str(args)
+    args.map{|a| Priter.new.print(a)}.join(" ")
   end
 
   def str(args)
-    args.map{|a| pr_str(a, false)}.join
+    args.map{|a| Printer.new(false).print(a)}.join
   end
 
   def prn(args)
-    puts self.pr_str_(args)
+    puts self.pr_str(args)
     nil
   end
 
   def println(args)
-    puts args.map{|a| pr_str(a, false)}.join(" ")
+    puts args.map{|a| Printer.new(false).print(a)}.join(" ")
     nil
   end
 
@@ -366,7 +366,7 @@ module Crisp
     ">"           => rel_op(:>)
     "<="          => rel_op(:<=)
     ">="          => rel_op(:>=)
-    "pr-str"      => func(:pr_str_)
+    "pr-str"      => func(:pr_str)
     "str"         => func(:str)
     "prn"         => func(:prn)
     "println"     => func(:println)

src/crisp/env.cr

@@ -6,7 +6,7 @@ module Crisp
   class Env
     property data
 
-    def initialize(@outer)
+    def initialize(@outer = nil)
       @data = {} of String => Crisp::Type
     end
 
@@ -50,8 +50,7 @@ module Crisp
     def find(key)
       return self if @data.has_key? key
 
-      o = @outer
-      if o
+      if o = @outer
         o.find key
       else
         nil

src/crisp/interpreter.cr

@@ -15,16 +15,16 @@ module Crisp
 
   class Interpreter
     def initialize(args)
-      @env = Crisp::Env.new nil
+      @env = Crisp::Env.new
 
       Crisp::NameSpace.each{|k,v| @curent_env.set(k, Crisp::Type.new(v))}
       @env.set("eval", Crisp::Type.new -> (args: Array(Crisp::Type)){ eval(args[0], @env) })
 
-      rep "(def! not (fn* (a) (if a false true)))"
-      rep "(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))"
-      rep "(defmacro! cond (fn* (& xs) (if (> (count xs) 0) (list 'if (first xs) (if (> (count xs) 1) (nth xs 1) (throw \"odd number of forms to cond\")) (cons 'cond (rest (rest xs)))))))"
-      rep "(defmacro! or (fn* (& xs) (if (empty? xs) nil (if (= 1 (count xs)) (first xs) `(let* (or_FIXME ~(first xs)) (if or_FIXME or_FIXME (or ~@(rest xs))))))))"
-      rep "(def! *host-language* \"crystal\")"
+      eval_string "(def! not (fn* (a) (if a false true)))"
+      eval_string "(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))"
+      eval_string "(defmacro! cond (fn* (& xs) (if (> (count xs) 0) (list 'if (first xs) (if (> (count xs) 1) (nth xs 1) (throw \"odd number of forms to cond\")) (cons 'cond (rest (rest xs)))))))"
+      eval_string "(defmacro! or (fn* (& xs) (if (empty? xs) nil (if (= 1 (count xs)) (first xs) `(let* (or_FIXME ~(first xs)) (if or_FIXME or_FIXME (or ~@(rest xs))))))))"
+      eval_string "(def! *host-language* \"crystal\")"
 
       argv = Crisp::List.new
 
@@ -35,6 +35,8 @@ module Crisp
       end
 
       @env.set("*ARGV*", Crisp::Type.new argv)
+
+      @printer = Printer.new
     end
 
     def func_of(env, binds, body)
@@ -259,22 +261,22 @@ module Crisp
     end
 
     def print(result)
-        n">pr_str(result, true)
+        vi">@printer.print(result)
     end
 
-    private def rep(str)
+    def eval_string(str)
       print(eval(read(str), @env))
     end
 
     def run(filename = nil)
       if filename
-        rep "(load-file \"#{filename}\")"
+        eval_string "(load-file \"#{filename}\")"
         return
       end
 
       while line = Readline.readline("Crisp> ", true)
         begin
-          puts rep(line)
+          puts eval_string(line)
         rescue e
           STDERR.puts e
         end

src/crisp/printer.cr

@@ -1,38 +1,41 @@
 require "./types"
 
 module Crisp
-  extend self
+  class Printer
+    def initialize(@print_readably = true)
+    end
 
-  def pr_str(value, print_readably = true)
-    case value
-    when Nil          then "nil"
-    when Bool         then value.to_s
-    when Int32        then value.to_s
-    when Crisp::List    then "(#{value.map{|v| pr_str(v, print_readably) as String}.join(" ")})"
-    when Crisp::Vector  then "[#{value.map{|v| pr_str(v, print_readably) as String}.join(" ")}]"
-    when Crisp::Symbol  then value.str.to_s
-    when Crisp::Func    then "<function>"
-    when Crisp::Closure then "<closure>"
-    when Crisp::HashMap
-      # step1_read_print.cr requires specifying type
-      "{#{value.map{|k, v| "#{pr_str(k, print_readably)} #{pr_str(v, print_readably)}" as String}.join(" ")}}"
-    when String
-      case
-      when value.empty?()
-        print_readably ? value.inspect : value
-      when value[0] == '\u029e'
-        ":#{value[1..-1]}"
-      else
-        print_readably ? value.inspect : value
-      end
-    when Crisp::Atom
-      "(atom #{pr_str(value.val, print_readably)})"
-    else
-      raise "invalid CrispType: #{value.to_s}"
+    def print(value)
+        case value
+        when Nil          then "nil"
+        when Bool         then value.to_s
+        when Int32        then value.to_s
+        when Crisp::List    then "(#{value.map{|v| pr_str(v, @print_readably) as String}.join(" ")})"
+        when Crisp::Vector  then "[#{value.map{|v| pr_str(v, @print_readably) as String}.join(" ")}]"
+        when Crisp::Symbol  then value.str.to_s
+        when Crisp::Func    then "<function>"
+        when Crisp::Closure then "<closure>"
+        when Crisp::HashMap
+        # step1_read_print.cr requires specifying type
+        "{#{value.map{|k, v| "#{pr_str(k, @print_readably)} #{pr_str(v, @print_readably)}" as String}.join(" ")}}"
+        when String
+        case
+        when value.empty?()
+            @print_readably ? value.inspect : value
+        when value[0] == '\u029e'
+            ":#{value[1..-1]}"
+        else
+            @print_readably ? value.inspect : value
+        end
+        when Crisp::Atom
+        "(atom #{pr_str(value.val, @print_readably)})"
+        else
+        raise "invalid CrispType: #{value.to_s}"
+        end
     end
-  end
 
-  def pr_str(t : Crisp::Type, print_readably = true)
-    pr_str(t.unwrap, print_readably) + (t.macro? ? " (macro)" : "")
+    def print(t : Crisp::Type)
+        print(t.unwrap, @print_readably) + (t.macro? ? " (macro)" : "")
+    end
   end
 end

src/crisp/types.cr

@@ -65,7 +65,7 @@ module Crisp
     end
 
     def to_s
-      pr_str(self)
+      Printer.new.print(self)
     end
 
     def dup