From: Florian Frank <flori@...>
Date: 2002-08-29T22:46:16+09:00
Subject: Re: Newbie converting brain from perl


--=-m82svbvaD7u2IgR4djuV
Content-Type: text/plain
Content-Transfer-Encoding: 7bit

On Wed, 2002-08-28 at 22:31, William Pietri wrote:
> 
> Howdy! As a long time Perl, Java, and Objective-C developer, I'm quite taken 
> with Ruby, and I'm busily converting my brain over. But there's a Perl 
> idiom that I'm having trouble translating. In Perl it goes like this:
> 
>     $date = "28 Aug 2002";
>     ($day, $month, $year) = $date =~ /(\d+) (\w+) (\d+)/;
> 
> 
> In Ruby the best I've been able to do is this:
> 
>     date = "28 Aug 2002"
>     day, month, year = /(\d+) (\w+) (\d+)/.match(date)[1..3]
> 
> But that final [1..3] thing seems inelegant, which makes me think I'm 
> barking up the wrong tree. What's the best Ruby-style way to do this?

I stumbled over this problem before. I think there isn't a really
elegant solution for this right now.

Adding MatchDate#captures to ruby would be possible though without
breaking much existing code:

/(\d+) (\w+) (\d+)/.match("28 Aug 2002").captures
    ==>["28", "Aug", "2002"]

I've made a little patch for this behaviour (attachment).

-- 
There is no God, and Murphy is his prophet.

--=-m82svbvaD7u2IgR4djuV
Content-Disposition: attachment; filename=re-captures.patch
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain; name=re-captures.patch; charset=ISO-8859-15

Index: re.c
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
RCS file: /src/ruby/re.c,v
retrieving revision 1.78
diff -u -r1.78 re.c
--- re.c	2002/08/29 09:08:16	1.78
+++ re.c	2002/08/29 13:19:57
@@ -898,6 +898,15 @@
 }
=20
 static VALUE
+match_captures(match)
+    VALUE match;
+{
+    VALUE ary =3D match_to_a(match);
+    rb_ary_shift(ary);
+    return ary;
+}
+
+static VALUE
 match_aref(argc, argv, match)
     int argc;
     VALUE *argv;
@@ -1615,6 +1624,7 @@
     rb_define_method(rb_cMatch, "end", match_end, 1);
     rb_define_method(rb_cMatch, "to_a", match_to_a, 0);
     rb_define_method(rb_cMatch, "to_ary", match_to_a, 0);
+    rb_define_method(rb_cMatch, "captures", match_captures, 0);
     rb_define_method(rb_cMatch, "[]", match_aref, -1);
     rb_define_method(rb_cMatch, "select", match_select, -1);
     rb_define_method(rb_cMatch, "pre_match", rb_reg_match_pre, 0);

--=-m82svbvaD7u2IgR4djuV--