5 files changed, 49 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog
index 5119ab0b01..38458917c4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Tue Apr 22 21:24:32 2008  Akinori MUSHA  <knu@iDaemons.org>
+
+	* eval.c (rb_proc_new): Turn the BLOCK_LAMBDA flag on.
+
+	* object.c (sym_to_proc), test/ruby/test_symbol.rb: Add back
+	  Symbol#to_proc, now that it passes the tests.
+
 Tue Apr 22 19:35:03 2008  Akinori MUSHA  <knu@iDaemons.org>
 
 	* enumerator.c (enumerator_initialize): Remove an undocumented
diff --git a/NEWS b/NEWS
index 0a8fe6836b..44ddaf05d6 100644
--- a/NEWS
+++ b/NEWS
@@ -232,6 +232,10 @@ with all sufficient information, see the ChangeLog file.
 
     Return an enumerator if no block is given.
 
+  * Symbol#to_proc
+
+    New method.
+
   * __method__
 
     New global function that returns the name of the current method as
diff --git a/eval.c b/eval.c
index e439768090..a9eb3d38c1 100644
--- a/eval.c
+++ b/eval.c
@@ -9636,6 +9636,7 @@ rb_proc_new(func, val)
 
     Data_Get_Struct(proc, struct BLOCK, data);
     data->body->nd_state = YIELD_FUNC_AVALUE;
+    data->flags |= BLOCK_LAMBDA;
     return proc;
 }
 
diff --git a/object.c b/object.c
index 28b7e4c84e..1d38798005 100644
--- a/object.c
+++ b/object.c
@@ -1212,6 +1212,35 @@ sym_to_sym(sym)
 }
 
 
+static VALUE
+sym_call(args, mid)
+    VALUE args, mid;
+{
+    VALUE obj;
+
+    if (RARRAY(args)->len < 1) {
+	rb_raise(rb_eArgError, "no receiver given");
+    }
+    obj = rb_ary_shift(args);
+    return rb_apply(obj, (ID)mid, args);
+}
+
+/*
+ * call-seq:
+ *   sym.to_proc
+ *
+ * Returns a _Proc_ object which respond to the given method by _sym_.
+ *
+ *   (1..3).collect(&:to_s)  #=> ["1", "2", "3"]
+ */
+
+static VALUE
+sym_to_proc(VALUE sym)
+{
+    return rb_proc_new(sym_call, (VALUE)SYM2ID(sym));
+}
+
+
 /***********************************************************************
  *
  * Document-class: Module
@@ -2755,6 +2784,7 @@ Init_Object()
     rb_define_method(rb_cSymbol, "to_s", sym_to_s, 0);
     rb_define_method(rb_cSymbol, "id2name", sym_to_s, 0);
     rb_define_method(rb_cSymbol, "to_sym", sym_to_sym, 0);
+    rb_define_method(rb_cSymbol, "to_proc", sym_to_proc, 0);
     rb_define_method(rb_cSymbol, "===", rb_obj_equal, 1); 
 
     rb_define_method(rb_cModule, "freeze", rb_mod_freeze, 0);
diff --git a/test/ruby/test_symbol.rb b/test/ruby/test_symbol.rb
index 2ccfe64c92..ac73dc9137 100644
--- a/test/ruby/test_symbol.rb
+++ b/test/ruby/test_symbol.rb
@@ -74,4 +74,11 @@ class TestSymbol < Test::Unit::TestCase
     assert_inspect_evaled(':$0')
     assert_inspect_evaled(':$1')
   end
+
+  def test_to_proc
+    assert_equal %w(1 2 3), (1..3).map(&:to_s)
+    assert_nothing_raised(ArgumentError) { :object_id.to_proc.call([]) }
+    assert_nothing_raised(ArgumentError) { :object_id.to_proc.call([1]) }
+    assert_nothing_raised(ArgumentError) { :object_id.to_proc.call([1,2]) }
+  end
 end