Clarification: use encoding cannot be used to

[p5sagit/p5-mst-13.2.git] / pod / perlfaq3.pod

diff --git a/pod/perlfaq3.pod b/pod/perlfaq3.pod
index efa764d..e4d03fb 100644 (file)
--- a/pod/perlfaq3.pod
+++ b/pod/perlfaq3.pod
@@ -1,6 +1,6 @@
 =head1 NAME
 
-perlfaq3 - Programming Tools ($Revision: 1.4 $, $Date: 2001/10/02 19:42:02 $)
+perlfaq3 - Programming Tools ($Revision: 1.8 $, $Date: 2001/10/17 14:14:20 $)
 
 =head1 DESCRIPTION
 
@@ -164,9 +164,13 @@ related to generating nicely printed output of documents.
 
 =head2 Is there a ctags for Perl?
 
-There's a simple one at
+Recent versions of ctags do much more than older versions did.
+EXUBERANT CTAGS is available from http://ctags.sourceforge.net/
+and does a good job of making tags files for perl code.
+
+There is also a simple one at
 http://www.perl.com/CPAN/authors/id/TOMC/scripts/ptags.gz which may do
-the trick.  And if not, it's easy to hack into what you want.
+the trick.  It can be easy to hack this into what you want.
 
 =head2 Is there an IDE or Windows Perl Editor?
 
@@ -232,7 +236,21 @@ and possibly an emacs too, so you may not need to download anything.
 In any emacs the cperl-mode (M-x cperl-mode) gives you perhaps the
 best available Perl editing mode in any editor.
 
-For Windows editors: you can download an Emacs
+If you are using Windows, you can use any editor that lets
+you work with plain text, such as NotePad or WordPad.  Word
+processors, such as Microsoft Word or WordPerfect, typically
+do not work since they insert all sorts of behind-the-scenes
+information, although some allow you to save files as "Text
+Only". You can also download text editors designed
+specifically for programming, such as Textpad
+(http://www.textpad.com/) and UltraEdit
+(http://www.ultraedit.com), among others.
+
+If you are using MacOS, the same concerns apply.  MacPerl
+(for Classic environments) comes with a simple editor.
+Popular external editors are BBEdit (http://www.bbedit.com)
+or Alpha (http://alpha.olm.net/). MacOS X users can use Unix
+editors as well.
 
 =over 4
 
@@ -519,6 +537,51 @@ When the files you're processing are small, it doesn't much matter which
 way you do it, but it makes a huge difference when they start getting
 larger. 
 
+=item * Use map and grep selectively
+
+Remember that both map and grep expect a LIST argument, so doing this:
+
+        @wanted = grep {/pattern/} <FILE>;
+
+will cause the entire file to be slurped. For large files, it's better
+to loop:
+
+        while (<FILE>) {
+                push(@wanted, $_) if /pattern/;
+        }
+
+=item * Avoid unnecessary quotes and stringification
+
+Don't quote large strings unless absolutely necessary:
+
+        my $copy = "$large_string";
+
+makes 2 copies of $large_string (one for $copy and another for the
+quotes), whereas
+
+        my $copy = $large_string;
+
+only makes one copy.
+
+Ditto for stringifying large arrays:
+
+        {
+                local $, = "\n";
+                print @big_array;
+        }
+
+is much more memory-efficient than either
+
+        print join "\n", @big_array;
+
+or
+
+        {
+                local $" = "\n";
+                print "@big_array";
+        }
+
+
 =item * Pass by reference
 
 Pass arrays and hashes by reference, not by value. For one thing, it's
@@ -806,30 +869,11 @@ For modules, get the CGI or LWP modules from CPAN.  For textbooks,
 see the two especially dedicated to web stuff in the question on
 books.  For problems and questions related to the web, like ``Why
 do I get 500 Errors'' or ``Why doesn't it run from the browser right
-when it runs fine on the command line'', see these sources:
-
-    WWW Security FAQ
-        http://www.w3.org/Security/Faq/
-
-    Web FAQ
-        http://www.boutell.com/faq/
-
-    CGI FAQ
-        http://www.webthing.com/tutorials/cgifaq.html
-
-    HTTP Spec
-        http://www.w3.org/pub/WWW/Protocols/HTTP/
-
-    HTML Spec
-        http://www.w3.org/TR/REC-html40/
-        http://www.w3.org/pub/WWW/MarkUp/
-
-    CGI Spec
-        http://www.w3.org/CGI/
-
-    CGI Security FAQ
-        http://www.go2net.com/people/paulp/cgi-security/safe-cgi.txt
+when it runs fine on the command line'', see the troubleshooting
+guides and references in L<perlfaq9> or in the CGI MetaFAQ:
 
+       http://www.perl.org/CGI_MetaFAQ.html
+       
 =head2 Where can I learn about object-oriented Perl programming?
 
 A good place to start is L<perltoot>, and you can use L<perlobj>,