CN Perl Advent Calendar 2009-12-12

Devel::REPL

by Fayland Lam

Devel::REPL 由牛人 Matt S Trout 所开发。整个开发过程通过 blog 发布，极具参考价值。

http://chainsawblues.vox.com/library/post/a-perl-read-excute-print-loop-repl.html

http://chainsawblues.vox.com/library/post/writing-a-perl-read-eval-print-loop-repl---part-2.html

http://chainsawblues.vox.com/library/post/writing-a-perl-repl-part-3---lexical-environments.html

http://chainsawblues.vox.com/library/post/develrepl-part-4---script-options-rc-files-profiles-and-packaging.html

（上述地址需要爬墙）

[fayland@perl ~]$ re.pl

$ use WWW::Mechanize;

$ my $ua = WWW::Mechanize->new;
my ($jar,$parser);
$jar = HTTP::Cookies=HASH(0x90530bc);
$parser = undef;
$WWW_Mechanize1 = WWW::Mechanize=HASH(0x94d1da4);

$ my $resp = $ua->get('http://google.com');
$HTTP_Response1 = HTTP::Response=HASH(0x9694a14);

$ $_REPL->load_plugin('Timing');
1
$ $resp = $ua->get('http://google.com');
Took 0.152513027191162 seconds.
$HTTP_Response1 = HTTP::Response=HASH(0x96ad904);

$ $ua->cookie_jar->as_string;
Took 0.000859975814819336 seconds.
Set-Cookie3: NID="29=EGf4gTTIzOZkezAPclz4IQnixlbALIP3tBnjzoU05vmI81T4duI8a7hPD49gYpwcwCTPnFlZlbdoSGw0Bz7amPObGUcbkKlK3yRUrbEJWVyGS3aTUY4ECmfOkmc7C-UG"; path="/"; domain=.google.com; path_spec; expires="2010-06-12 13:21:07Z"; HttpOnly; version=0
Set-Cookie3: PREF="ID=2704ee5d6f52e4ca:U=34269efc86f19890:TM=1260537667:LM=1260537775:S=QZ3yjOx-nf6n6K5U"; path="/"; domain=.google.com; path_spec; expires="2011-12-11 13:22:55Z"; version=0

$ sub fact {

> my $n = shift;

> return 1 if $n < 2;

> return $n * fact($n-1);

> }

$ fact(10);
3628800

$ exit

本文只做简单介绍，更多更详尽的功能就需要自己去尝试。

另外，可以自定义 profile 模块或者 rc 文件来构建自己的 re.pl 环境。

基于该模块的扩展有 Carp::REPL 和 CatalystX::REPL，都是非常好的工具。

Enjoy! 谢谢。