From 0e20782339a5734dacbcdf4be78fd5b2745de1af Mon Sep 17 00:00:00 2001
From: matz <matz@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Mon, 15 Dec 2008 14:46:50 +0000
Subject: [PATCH] * ruby.c (process_options): revive global sub, gsub, chop,
 chomp   only when auto looping options (-p/-n) is specified.  
 [ruby-core:20570]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@20765 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog |  6 ++++
 ruby.c    | 98 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 104 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 064ec5229a..ce179579b6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,12 @@ Mon Dec 15 23:34:04 2008  Tanaka Akira  <akr@fsij.org>
 
 	* ext/pty/pty.c (pty_open): set FMODE_SYNC and FMODE_DUPLEX.
 
+Mon Dec 15 23:29:49 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* ruby.c (process_options): revive global sub, gsub, chop, chomp
+	  only when auto looping options (-p/-n) is specified.
+	  [ruby-core:20570]
+
 Mon Dec 15 22:48:11 2008  Tanaka Akira  <akr@fsij.org>
 
 	* ext/pty/pty.c (pty_open): new method PTY.open.
diff --git a/ruby.c b/ruby.c
index 805c36d9fc..24f1b706c3 100644
--- a/ruby.c
+++ b/ruby.c
@@ -1103,6 +1103,100 @@ true_value(void)
 #define rb_define_readonly_boolean(name, val) \
     rb_define_virtual_variable((name), (val) ? true_value : false_value, 0)
 
+static VALUE
+uscore_get()
+{
+    VALUE line;
+
+    line = rb_lastline_get();
+    if (TYPE(line) != T_STRING) {
+	rb_raise(rb_eTypeError, "$_ value need to be String (%s given)",
+		 NIL_P(line) ? "nil" : rb_obj_classname(line));
+    }
+    return line;
+}
+
+/*
+ *  call-seq:
+ *     sub(pattern, replacement)   => $_
+ *     sub(pattern) { block }      => $_
+ *  
+ *  Equivalent to <code>$_.sub(<i>args</i>)</code>, except that
+ *  <code>$_</code> will be updated if substitution occurs.
+ *  Available only when -p/-n command line option specified.
+ */
+
+static VALUE
+rb_f_sub(argc, argv)
+    int argc;
+    VALUE *argv;
+{
+    VALUE str = rb_funcall3(uscore_get(), rb_intern("sub"), argc, argv);
+    rb_lastline_set(str);
+    return str;
+}
+
+/*
+ *  call-seq:
+ *     gsub(pattern, replacement)    => string
+ *     gsub(pattern) {|...| block }  => string
+ *  
+ *  Equivalent to <code>$_.gsub...</code>, except that <code>$_</code>
+ *  receives the modified result.
+ *  Available only when -p/-n command line option specified.
+ *     
+ */
+
+static VALUE
+rb_f_gsub(argc, argv)
+    int argc;
+    VALUE *argv;
+{
+    VALUE str = rb_funcall3(uscore_get(), rb_intern("gsub"), argc, argv);
+    rb_lastline_set(str);
+    return str;
+}
+
+/*
+ *  call-seq:
+ *     chop   => string
+ *  
+ *  Equivalent to <code>($_.dup).chop!</code>, except <code>nil</code>
+ *  is never returned. See <code>String#chop!</code>.
+ *  Available only when -p/-n command line option specified.
+ *     
+ */
+
+static VALUE
+rb_f_chop()
+{
+    VALUE str = rb_funcall3(uscore_get(), rb_intern("chop"), 0, 0);
+    rb_lastline_set(str);
+    return str;
+}
+
+
+/*
+ *  call-seq:
+ *     chomp            => $_
+ *     chomp(string)    => $_
+ *  
+ *  Equivalent to <code>$_ = $_.chomp(<em>string</em>)</code>. See
+ *  <code>String#chomp</code>.
+ *  Available only when -p/-n command line option specified.
+ *     
+ */
+
+static VALUE
+rb_f_chomp(argc, argv)
+    int argc;
+    VALUE *argv;
+{
+    VALUE str = rb_funcall3(uscore_get(), rb_intern("chomp"), argc, argv);
+    rb_lastline_set(str);
+    return str;
+}
+
 static VALUE
 process_options(VALUE arg)
 {
@@ -1282,6 +1376,10 @@ process_options(VALUE arg)
     }
     if (opt->do_loop) {
 	tree = rb_parser_while_loop(parser, tree, opt->do_line, opt->do_split);
+	rb_define_global_function("sub", rb_f_sub, -1);
+	rb_define_global_function("gsub", rb_f_gsub, -1);
+	rb_define_global_function("chop", rb_f_chop, 0);
+	rb_define_global_function("chomp", rb_f_chomp, -1);
     }
 
     iseq = rb_iseq_new_top(tree, rb_str_new2("<main>"),