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Log::Report::Dispatcher::Try(3pm) User Contributed Perl Documentation Log::Report::Dispatcher::Try(3pm)

Log::Report::Dispatcher::Try - capture all reports as exceptions

 Log::Report::Dispatcher::Try
   is a Log::Report::Dispatcher


 try { ... };       # mind the ';' !!
 if($@) {           # signals something went wrong
 if(try {...}) {    # block ended normally
 my $x = try { read_temperature() };
 my @x = try { read_lines_from_file() };
 try { ... }        # no comma!!
    mode => 'DEBUG', accept => 'ERROR-';
 try sub { ... },   # with comma
    mode => 'DEBUG', accept => 'ALL';
 try \&myhandler, accept => 'ERROR-';
 try { ... } hide => 'TRACE';
 print ref $@;      # Log::Report::Dispatcher::Try
 $@->reportFatal;   # re-dispatch result of try block
 $@->reportAll;     # ... also warnings etc
 if($@) {...}       # if errors
 if($@->failed) {   # same       # }
 if($@->success) {  # no errors  # }
 try { # something causes an error report, which is caught
       failure 'no network';
     };
 $@->reportFatal(to => 'syslog');  # overrule destination
 print $@->exceptions; # no re-cast, just print

The Log::Report::try() catches errors in the block (CODE reference) which is just following the function name. All dispatchers are temporarily disabled by "try", and messages which are reported are collected within a temporary dispatcher named "try". When the CODE has run, that "try" dispatcher is returned in $@, and all original dispatchers reinstated.

Then, after the "try" has finished, the routine which used the "try" should decide what to do with the collected reports. These reports are collected as Log::Report::Exception objects. They can be ignored, or thrown to a higher level try... causing an exit of the program if there is none.

Extends "DESCRIPTION" in Log::Report::Dispatcher.

Extends "METHODS" in Log::Report::Dispatcher.

Extends "Constructors" in Log::Report::Dispatcher.

$obj->close()
Inherited, see "Constructors" in Log::Report::Dispatcher
 -Option       --Defined in             --Default
  accept         Log::Report::Dispatcher  depend on mode
  charset        Log::Report::Dispatcher  <undef>
  died                                    undef
  exceptions                              []
  format_reason  Log::Report::Dispatcher  'LOWERCASE'
  hide                                    'NONE'
  locale         Log::Report::Dispatcher  <system locale>
  mode           Log::Report::Dispatcher  'NORMAL'
  on_die                                  'ERROR'
The exit string ($@) of the eval'ed block.
ARRAY of Log::Report::Exception objects.
[1.09] see hide()
When code which runs in this block exits with a die(), it will get translated into a Log::Report::Exception using Log::Report::Die::die_decode(). How serious are we about these errors?

Extends "Accessors" in Log::Report::Dispatcher.

$obj->die2reason()
Returns the value of new(on_die).
$obj->died( [STRING] )
The message which was reported by "eval", which is used internally to catch problems in the try block.
$obj->exceptions()
Returns all collected "Log::Report::Exceptions". The last of them may be a fatal one. The other are non-fatal.
$obj->hide(REASON|REASONS|ARRAY|'ALL'|'NONE')
[1.09] By default, the try will only catch messages which stop the execution of the block (errors etc, internally a 'die'). Other messages are passed to parent try blocks, if none than to the dispatchers.

This option gives the opportunity to block, for instance, trace messages. Those messages are still collected inside the try object, so may get passed-on later via reportAll() if you like.

Be warned: Using this method will reset the whole 'hide' configuration: it's a set not an add.

example: change the setting of the running block

  my $parent_try = dispatcher 'active-try';
  parent_try->hide('NONE');
$obj->hides(REASON)
$obj->isDisabled()
Inherited, see "Accessors" in Log::Report::Dispatcher
$obj->mode()
Inherited, see "Accessors" in Log::Report::Dispatcher
$obj->name()
Inherited, see "Accessors" in Log::Report::Dispatcher
$obj->needs( [$reason] )
Inherited, see "Accessors" in Log::Report::Dispatcher
$obj->type()
Inherited, see "Accessors" in Log::Report::Dispatcher

Extends "Logging" in Log::Report::Dispatcher.

$obj->addSkipStack(@CODE)
Inherited, see "Logging" in Log::Report::Dispatcher
$obj->collectLocation()
Inherited, see "Logging" in Log::Report::Dispatcher
$obj->collectStack( [$maxdepth] )
Inherited, see "Logging" in Log::Report::Dispatcher
$obj->log($opts, $reason, $message)
Other dispatchers translate the message here, and make it leave the program. However, messages in a "try" block are only captured in an intermediate layer: they may never be presented to an end-users. And for sure, we do not know the language yet.

The $message is either a STRING or a Log::Report::Message.

$obj->reportAll(%options)
Re-cast the messages in all collect exceptions into the defined dispatchers, which were disabled during the try block. The %options will end-up as HASH of %options to Log::Report::report(); see Log::Report::Exception::throw() which does the job.
$obj->reportFatal()
Re-cast only the fatal message to the defined dispatchers. If the block was left without problems, then nothing will be done. The %options will end-up as HASH of %options to Log::Report::report(); see Log::Report::Exception::throw() which does the job.
$obj->skipStack()
Inherited, see "Logging" in Log::Report::Dispatcher
$obj->stackTraceLine(%options)
Inherited, see "Logging" in Log::Report::Dispatcher
$obj->translate(HASH-$of-%options, $reason, $message)
Inherited, see "Logging" in Log::Report::Dispatcher

$obj->failed()
Returns true if the block was left with an fatal message.
$obj->showStatus()
If this object is kept in $@, and someone uses this as string, we want to show the fatal error message.

The message is not very informative for the good cause: we do not want people to simply print the $@, but wish for a re-cast of the message using reportAll() or reportFatal().

$obj->success()
Returns true if the block exited normally.
$obj->wasFatal(%options)
Returns the Log::Report::Exception which caused the "try" block to die, otherwise an empty LIST (undef). 

 -Option--Default
  class   undef
Only return the exception if it was fatal, and in the same time in the specified CLASS (as string) or matches the REGEX. See Log::Report::Message::inClass()

Extends "DETAILS" in Log::Report::Dispatcher.

Returns true if the previous try block did produce a terminal error. This "try" object is assigned to $@, and the usual perl syntax is "if($@) {...error-handler...}".
When $@ is used the traditional way, it is checked to have a string content. In this case, stringify into the fatal error or nothing.

This module is part of Log-Report distribution version 1.27, built on June 01, 2018. Website: http://perl.overmeer.net/CPAN/

Copyrights 2007-2018 by [Mark Overmeer <markov@cpan.org>]. For other contributors see ChangeLog.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See http://dev.perl.org/licenses/

2018-07-29 perl v5.26.2