Change 16653: FAQ sync.

[Jarkko Hietaniemi]

Change 16653 by jhi@alpha on 2002/05/17 12:18:54

        FAQ sync.

Affected files ...

..... //depot/perl/pod/perlfaq4.pod#72 edit
..... //depot/perl/pod/perlfaq8.pod#35 edit

Differences ...

==== //depot/perl/pod/perlfaq4.pod#72 (text) ====
Index: perl/pod/perlfaq4.pod
--- perl/pod/perlfaq4.pod#71~16527~     Thu May  9 07:09:00 2002
+++ perl/pod/perlfaq4.pod       Fri May 17 05:18:54 2002
@@ -1,6 +1,6 @@
 =head1 NAME
 
-perlfaq4 - Data Manipulation ($Revision: 1.21 $, $Date: 2002/05/06 13:08:46 $)
+perlfaq4 - Data Manipulation ($Revision: 1.22 $, $Date: 2002/05/16 12:44:24 $)
 
 =head1 DESCRIPTION
 
@@ -1396,13 +1396,20 @@
        $_ *= (4/3) * 3.14159;  # this will be constant folded
     }
 
-If you want to do the same thing to modify the values of the hash,
-you may not use the C<values> function, oddly enough.  You need a slice:
+If you want to do the same thing to modify the values of the
+hash, you can use the C<values> function.  As of Perl 5.6
+the values are not copied, so if you modify $orbit (in this
+case), you modify the value.
 
-    for $orbit ( @orbits{keys %orbits} ) {
+    for $orbit ( values %orbits ) {
        ($orbit **= 3) *= (4/3) * 3.14159; 
     }
-
+    
+Prior to perl 5.6 C<values> returned copies of the values,
+so older perl code often contains constructions such as
+C<@orbits{keys %orbits}> instead of C<values %orbits> where
+the hash is to be modified.
+    
 =head2 How do I select a random element from an array?
 
 Use the rand() function (see L<perlfunc/rand>):
@@ -1539,6 +1546,13 @@
 
 This method gets faster the more sparse the bit vector is.
 (Courtesy of Tim Bunce and Winfried Koenig.)
+
+You can make the while loop a lot shorter with this suggestion
+from Benjamin Goldberg:
+
+       while($vec =~ /[^\0]+/g ) {
+          push @ints, grep vec($vec, $_, 1), $-[0] * 8 .. $+[0] * 8;
+       }
 
 Or use the CPAN module Bit::Vector:
 

==== //depot/perl/pod/perlfaq8.pod#35 (text) ====
Index: perl/pod/perlfaq8.pod
--- perl/pod/perlfaq8.pod#34~16113~     Tue Apr 23 15:38:04 2002
+++ perl/pod/perlfaq8.pod       Fri May 17 05:18:54 2002
@@ -1,6 +1,6 @@
 =head1 NAME
 
-perlfaq8 - System Interaction ($Revision: 1.7 $, $Date: 2002/04/18 14:23:15 $)
+perlfaq8 - System Interaction ($Revision: 1.8 $, $Date: 2002/05/16 12:41:42 $)
 
 =head1 DESCRIPTION
 
@@ -968,9 +968,17 @@
 =head2 How do I install a module from CPAN?
 
 The easiest way is to have a module also named CPAN do it for you.
-This module comes with perl version 5.004 and later.  To manually install
-the CPAN module, or any well-behaved CPAN module for that matter, follow
-these steps:
+This module comes with perl version 5.004 and later.  
+
+    $ perl -MCPAN -e shell
+
+    cpan shell -- CPAN exploration and modules installation (v1.59_54)
+    ReadLine support enabled
+
+    cpan> install Some::Module 
+
+To manually install the CPAN module, or any well-behaved CPAN module 
+for that matter, follow these steps:
 
 =over 4
 
End of Patch.