* numeric.c (int_odd_p): a new method to check even or odd.

  [RCR#337]

* numeric.c (int_even_p): ditto.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@10982 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 68 insertions, 0 deletions

diff --git a/numeric.c b/numeric.c
index cab949babc..5f0e10f64a 100644
--- a/numeric.c
+++ b/numeric.c
@@ -1700,6 +1700,38 @@ int_int_p(VALUE num)
 
 /*
  *  call-seq:
+ *     int.odd? -> true or false
+ *  
+ *  Returns <code>true</code> if <i>int</i> is an odd number.
+ */
+
+static VALUE
+int_odd_p(VALUE num)
+{
+    if (rb_funcall(num, '%', 1, INT2FIX(2)) != INT2FIX(0)) {
+	return Qtrue;
+    }
+    return Qfalse;
+}
+
+/*
+ *  call-seq:
+ *     int.even? -> true or false
+ *  
+ *  Returns <code>true</code> if <i>int</i> is an even number.
+ */
+
+static VALUE
+int_even_p(VALUE num)
+{
+    if (rb_funcall(num, '%', 1, INT2FIX(2)) == INT2FIX(0)) {
+	return Qtrue;
+    }
+    return Qfalse;
+}
+
+/*
+ *  call-seq:
  *     int.next    => integer
  *     int.succ    => integer
  *  
@@ -2799,6 +2831,38 @@ fix_zero_p(VALUE num)
     return Qfalse;
 }
 
+/*
+ *  call-seq:
+ *     fix.odd? -> true or false
+ *  
+ *  Returns <code>true</code> if <i>fix</i> is an odd number.
+ */
+
+static VALUE
+fix_odd_p(VALUE num)
+{
+    if (num & 2) {
+	return Qtrue;
+    }
+    return Qfalse;
+}
+
+/*
+ *  call-seq:
+ *     fix.even? -> true or false
+ *  
+ *  Returns <code>true</code> if <i>fix</i> is an even number.
+ */
+
+static VALUE
+fix_even_p(VALUE num)
+{
+    if (num & 2) {
+	return Qfalse;
+    }
+    return Qtrue;
+}
+
 void
 Init_Numeric(void)
 {
@@ -2853,6 +2917,8 @@ Init_Numeric(void)
     rb_undef_method(CLASS_OF(rb_cInteger), "new");
 
     rb_define_method(rb_cInteger, "integer?", int_int_p, 0);
+    rb_define_method(rb_cInteger, "odd?", int_odd_p, 0);
+    rb_define_method(rb_cInteger, "even?", int_even_p, 0);
     rb_define_method(rb_cInteger, "upto", int_upto, 1);
     rb_define_method(rb_cInteger, "downto", int_downto, 1);
     rb_define_method(rb_cInteger, "times", int_dotimes, 0);
@@ -2910,6 +2976,8 @@ Init_Numeric(void)
     rb_define_method(rb_cFixnum, "to_f", fix_to_f, 0);
     rb_define_method(rb_cFixnum, "size", fix_size, 0);
     rb_define_method(rb_cFixnum, "zero?", fix_zero_p, 0);
+    rb_define_method(rb_cInteger, "odd?", fix_odd_p, 0);
+    rb_define_method(rb_cInteger, "even?", fix_even_p, 0);
 
     rb_cFloat  = rb_define_class("Float", rb_cNumeric);