5 use namespace::autoclean;
6 use 5.008001; # backwards compat, doesn't warn like 5.8.1
8 our $VERSION = '1.003018';
10 with 'MooseX::Object::Pluggable';
12 use Devel::REPL::Error;
17 default => sub { Term::ReadLine->new('Perl REPL') }
22 default => sub { '$ ' }
28 default => sub { shift->term->OUT || \*STDOUT; }
38 while ($self->run_once_safely) {
39 # keep looping unless we want to exit REPL
40 last if $self->exit_repl;
45 my ($self, @args) = @_;
47 my $ret = eval { $self->run_once(@args) };
51 eval { $self->print("Error! - $error\n"); };
61 my $line = $self->read;
62 return unless defined($line); # undefined value == EOF
64 my @ret = $self->formatted_eval($line);
66 $self->print(@ret) unless $self->exit_repl;
72 my ( $self, @args ) = @_;
74 my @ret = $self->eval(@args);
76 return $self->format(@ret);
80 my ( $self, @stuff ) = @_;
82 if ( $self->is_error($stuff[0]) ) {
83 return $self->format_error(@stuff);
85 return $self->format_result(@stuff);
90 my ( $self, @stuff ) = @_;
96 my ( $self, $error ) = @_;
97 return $error->stringify;
101 my ( $self, $thingy ) = @_;
102 blessed($thingy) and $thingy->isa("Devel::REPL::Error");
107 return $self->term->readline($self->prompt);
111 my ($self, $line) = @_;
112 my $compiled = $self->compile($line);
113 return $compiled unless defined($compiled) and not $self->is_error($compiled);
114 return $self->execute($compiled);
118 my ( $_REPL, @args ) = @_;
119 my $compiled = eval $_REPL->wrap_as_sub(@args);
120 return $_REPL->error_return("Compile error", $@) if $@;
125 my ($self, $line, %args) = @_;
126 return qq!sub {\n!. ( $args{no_mangling} ? $line : $self->mangle_line($line) ).qq!\n}\n!;
130 my ($self, $line) = @_;
135 my ($self, $to_exec, @args) = @_;
136 my @ret = eval { $to_exec->(@args) };
137 return $self->error_return("Runtime error", $@) if $@;
142 my ($self, $type, $error) = @_;
143 return Devel::REPL::Error->new( type => $type, message => $error );
147 my ($self, @ret) = @_;
148 my $fh = $self->out_fh;
149 no warnings 'uninitialized';
151 print $fh "\n" if $self->term->ReadLine =~ /Gnu/;
156 Devel::REPL - a modern perl interactive shell
160 my $repl = Devel::REPL->new;
161 $repl->load_plugin($_) for qw(History LexEnv);
164 Alternatively, use the 're.pl' script installed with the distribution
170 This is an interactive shell for Perl, commonly known as a REPL - Read,
171 Evaluate, Print, Loop. The shell provides for rapid development or testing
172 of code without the need to create a temporary source code file.
174 Through a plugin system, many features are available on demand. You can also
175 tailor the environment through the use of profiles and run control files, for
176 example to pre-load certain Perl modules when working on a particular project.
180 To start a shell, follow one of the examples in the L</"SYNOPSIS"> above.
182 Once running, the shell accepts and will attempt to execute any code given. If
183 the code executes successfully you'll be shown the result, otherwise an error
184 message will be returned. Here are a few examples:
186 $_ print "Hello, world!\n"
190 Compile error: Bareword "nosuchfunction" not allowed while "strict subs" in use at (eval 130) line 5.
194 In the first example above you see the output of the command (C<Hello,
195 world!>), if any, and then the return value of the statement (C<1>). Following
196 that example, an error is returned when the execution of some code fails.
198 Note that the lack of semicolon on the end is not a mistake - the code is
199 run inside a Block structure (to protect the REPL in case the code blows up),
200 which means a single statement doesn't require the semicolon. You can add one
203 If you followed the first example in the L</"SYNOPSIS"> above, you'll have the
204 History and LexEnv plugins loaded (and there are many more available).
205 Although the shell might support "up-arrow" history, the History plugin adds
206 "bang" history to that so you can re-execute chosen commands (with e.g.
207 C<!53>). The LexEnv plugin ensures that lexical variables declared with the
208 C<my> keyword will automatically persist between statements executed in the
211 When you C<use> any Perl module, the C<import()> will work as expected - the
212 exported functions from that module are available for immediate use:
214 $_ carp "I'm dieeeing!\n"
215 String found where operator expected at (eval 129) line 5, near "carp "I'm dieeeing!\n""
216 (Do you need to predeclare carp?)
217 Compile error: syntax error at (eval 129) line 5, near "carp "I'm dieeeing!\n""
218 BEGIN not safe after errors--compilation aborted at (eval 129) line 5.
222 $_ carp "I'm dieeeing!\n"
224 at /usr/share/perl5/Lexical/Persistence.pm line 327
228 To quit from the shell, hit C<Ctrl+D> or C<Ctrl+C>.
230 MSWin32 NOTE: control keys won't work if TERM=dumb
231 because readline functionality will be disabled.
234 =head2 Run Control Files
236 For particular projects you might well end up running the same commands each
237 time the REPL shell starts up - loading Perl modules, setting configuration,
238 and so on. A run control file lets you have this done automatically, and you
239 can have multiple files for different projects.
241 By default the C<re.pl> program looks for C<< $HOME/.re.pl/repl.rc >>, and
242 runs whatever code is in there as if you had entered it at the REPL shell
245 To set a new run control file that's also in that directory, pass it as a
248 system$ re.pl --rcfile myproject.pc
250 If the filename happens to contain a forwardslash, then it's used absolutely,
251 or realive to the current working directory:
253 system$ re.pl --rcfile /path/to/my/project/repl.rc
255 Within the run control file you might want to load plugins. This is covered in
256 L</"The REPL shell object"> section, below.
260 To allow for the sharing of run control files, you can fashion them into a
261 Perl module for distribution (perhaps via the CPAN). For more information on
262 this feature, please see the L<Devel::REPL::Profile> manual page.
264 A default profile ships with C<Devel::REPL>; it loads the following plugins:
270 L<Devel::REPL::Plugin::History>
274 L<Devel::REPL::Plugin::LexEnv>
278 L<Devel::REPL::Plugin::DDS>
282 L<Devel::REPL::Plugin::Packages>
286 L<Devel::REPL::Plugin::Commands>
290 L<Devel::REPL::Plugin::MultiLine::PPI>
294 L<Devel::REPL::Plugin::Colors>
298 L<Devel::REPL::Plugin::Completion>
302 L<Devel::REPL::Plugin::CompletionDriver::INC>
306 L<Devel::REPL::Plugin::CompletionDriver::LexEnv>
310 L<Devel::REPL::Plugin::CompletionDriver::Keywords>
314 L<Devel::REPL::Plugin::CompletionDriver::Methods>
318 L<Devel::REPL::Plugin::ReadlineHistory>
324 Plugins are a way to add funcionality to the REPL shell, and take advantage of
325 C<Devel::REPL> being based on the L<Moose> object system for Perl 5. This
326 means it's simple to 'hook into' many steps of the R-E-P-L process. Plugins
327 can change the way commands are interpreted, or the way their results are
328 output, or even add commands to the shell environment.
330 A number of plugins ship with C<Devel::REPL>, and more are available on the
331 CPAN. Some of the shipped plugins are loaded in the default profile, mentioned
332 above. These plugins can be loaded in your C<< $HOME/.re.pl/repl.rc >> like:
334 load_plugin qw( CompletionDriver::Global DumpHistory );
336 Writing your own plugins is not difficult, and is discussed in the
337 L<Devel::REPL::Plugin> manual page, along with links to the manual pages of
338 all the plugins shipped with C<Devel::REPL>.
340 =head2 The REPL shell object
342 From time to time you'll want to interact with or manipulate the
343 C<Devel::REPL> shell object itself; that is, the instance of the shell you're
346 The object is always available through the C<$_REPL> variable. One common
347 requirement is to load an additional plugin, after your profile and run
348 control files have already been executed:
350 $_ $_REPL->load_plugin('Timing');
352 $_ print "Hello again, world!\n"
354 Took 0.00148296356201172 seconds.
360 In addition to the contents of the standard Perl distribution, you will need
371 L<MooseX::Object::Pluggable> >= 0.0009
375 L<MooseX::Getopt> >= 0.18
379 L<namespace::autoclean>
403 Optionally, some plugins if installed will require the following modules:
413 L<Data::Dump::Streamer>
417 L<Data::Dumper::Concise>
433 L<Lexical::Persistence>
447 Matt S Trout - mst (at) shadowcatsystems.co.uk (L<http://www.shadowcatsystems.co.uk/>)
453 =item Stevan Little - stevan (at) iinteractive.com
455 =item Alexis Sukrieh - sukria+perl (at) sukria.net
459 =item mgrimes - mgrimes (at) cpan dot org
461 =item Shawn M Moore - sartak (at) gmail.com
463 =item Oliver Gorwits - oliver on irc.perl.org
465 =item Andrew Moore - C<< <amoore@cpan.org> >>
467 =item Norbert Buchmuller C<< <norbi@nix.hu> >>
469 =item Dave Houston C<< <dhouston@cpan.org> >>
473 =item Karen Etheridge C<< <ether@cpan.org> >>
479 This library is free software under the same terms as perl itself