From 8418ea8bb86d5e205e3bc11c5d034e112418500e Mon Sep 17 00:00:00 2001
From: matz <matz@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Tue, 30 Jan 2007 04:27:04 +0000
Subject: * numeric.c (int_pred): add Integer#pred corresponding  
 Integer#succ.  [RCR#5]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@11596 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 numeric.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

(limited to 'numeric.c')

diff --git a/numeric.c b/numeric.c
index 43fbfe8638..aa5c275606 100644
--- a/numeric.c
+++ b/numeric.c
@@ -1766,6 +1766,26 @@ int_succ(VALUE num)
     return rb_funcall(num, '+', 1, INT2FIX(1));
 }
 
+/*
+ *  call-seq:
+ *     int.pred    => integer
+ *  
+ *  Returns the <code>Integer</code> equal to <i>int</i> - 1.
+ *     
+ *     1.pred      #=> 0
+ *     (-1).pred   #=> -2
+ */
+
+static VALUE
+int_pred(VALUE num)
+{
+    if (FIXNUM_P(num)) {
+	long i = FIX2LONG(num) - 1;
+	return LONG2NUM(i);
+    }
+    return rb_funcall(num, '-', 1, INT2FIX(1));
+}
+
 /*
  *  call-seq:
  *     int.chr    => string
@@ -2948,6 +2968,7 @@ Init_Numeric(void)
     rb_include_module(rb_cInteger, rb_mPrecision);
     rb_define_method(rb_cInteger, "succ", int_succ, 0);
     rb_define_method(rb_cInteger, "next", int_succ, 0);
+    rb_define_method(rb_cInteger, "pred", int_pred, 0);
     rb_define_method(rb_cInteger, "chr", int_chr, 0);
     rb_define_method(rb_cInteger, "to_i", int_to_i, 0);
     rb_define_method(rb_cInteger, "to_int", int_to_i, 0);
-- 
cgit v1.2.3