Data::Object::Try

Try Class for Perl 5

method: call method: callback method: catch method: default method: execute method: finally method: maybe method: no_catch method: no_default method: no_finally method: no_try method: result

use strict;
use warnings;
use routines;

use Data::Object::Try;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {
  # try something

  return time;
});

$try->catch('Example::Exception', fun ($caught) {
  # caught an exception

  return;
});

$try->default(fun ($caught) {
  # catch the uncaught

  return;
});

$try->finally(fun (@args) {
  # always run after try/catch

  return;
});

my @args;

my $result = $try->result(@args);

invocant: ro, opt, Object arguments: ro, opt, ArrayRef on_try: rw, opt, CodeRef on_catch: rw, opt, ArrayRef[CodeRef] on_default: rw, opt, CodeRef on_finally: rw, opt, CodeRef

This package provides an object-oriented interface for performing complex try/catch operations.

The call method takes a method name or coderef, registers it as the tryable routine, and returns the object. When invoked, the callback will received an invocant if one was provided to the constructor, the default arguments if any were provided to the constructor, and whatever arguments were provided by the invocant.

call(Str | CodeRef $arg) : Object

=example-1 call

use routines;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {

  return [@args];
});

The callback method takes a method name or coderef, and returns a coderef for registration. If a coderef is provided this method is mostly a passthrough.

callback(Str | CodeRef $arg) : CodeRef

=example-1 callback

use routines;

my $try = Data::Object::Try->new;

$try->callback(fun (@args) {

  return [@args];
});

=example-2 callback

package Example;

use Moo;
use routines;

fun test(@args) {

  return [@args];
}

package main;

my $try = Data::Object::Try->new(
  invocant => Example->new
);

$try->callback('test');

The catch method takes a package or ref name, and when triggered checks whether the captured exception is of the type specified and if so executes the given callback.

catch(Str $isa, Str | CodeRef $arg) : Any

=example-1 catch

use routines;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {

  die $try;
});

$try->catch('Data::Object::Try', fun (@args) {

  return [@args];
});

The default method takes a method name or coderef and is triggered if no catch conditions match the exception thrown.

default(Str | CodeRef $arg) : Object

=example-1 default

use routines;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {

  die $try;
});

$try->default(fun (@args) {

  return [@args];
});

The execute method takes a coderef and executes it with any given arguments. When invoked, the callback will received an invocant if one was provided to the constructor, the default arguments if any were provided to the constructor, and whatever arguments were passed directly to this method.

execute(CodeRef $arg, Any @args) : Any

=example-1 execute

use routines;

my $try = Data::Object::Try->new(
  invocant => Example->new,
  arguments => [1,2,3]
);

$try->execute(fun (@args) {

  return [@args];
});

The finally method takes a package or ref name and always executes the callback after a try/catch operation. The return value is ignored. When invoked, the callback will received an invocant if one was provided to the constructor, the default arguments if any were provided to the constructor, and whatever arguments were provided by the invocant.

finally(Str | CodeRef $arg) : Object

=example-1 finally

use routines;

my $try = Data::Object::Try->new(
  invocant => Example->new,
  arguments => [1,2,3]
);

$try->call(fun (@args) {

  return $try;
});

$try->finally(fun (@args) {

  $try->{'$finally'} = [@args];
});

The maybe method registers a default catch condition that returns falsy, i.e. an empty string, if an exception is encountered.

maybe() : Object

=example-1 maybe

use routines;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {

  die $try;
});

$try->maybe;

The no_catch method removes any configured catch conditions and returns the object.

no_catch() : Object

=example-1 no_catch

use routines;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {

  die $try;
});

$try->catch('Data::Object::Try', fun (@args) {

  return [@args];
});

$try->no_catch;

The no_default method removes any configured default condition and returns the object.

no_default() : Object

=example-1 no_default

use routines;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {

  die $try;
});

$try->default(fun (@args) {

  return [@args];
});

$try->no_default;

The no_finally method removes any configured finally condition and returns the object.

no_finally() : Object

=example-1 no_finally

use routines;

my $try = Data::Object::Try->new(
  invocant => Example->new,
  arguments => [1,2,3]
);

$try->call(fun (@args) {

  return $try;
});

$try->finally(fun (@args) {

  $try->{'$finally'} = [@args];
});

$try->no_finally;

The no_try method removes any configured try operation and returns the object.

no_try() : Object

=example-1 no_try

use routines;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {

  return [@args];
});

$try->no_try;

The result method executes the try/catch/default/finally logic and returns either 1) the return value from the successfully tried operation 2) the return value from the successfully matched catch condition if an exception was thrown 3) the return value from the default catch condition if an exception was thrown and no catch condition matched. When invoked, the try and finally callbacks will received an invocant if one was provided to the constructor, the default arguments if any were provided to the constructor, and whatever arguments were passed directly to this method.

result(Any @args) : Any

=example-1 result

use routines;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {

  return [@args];
});

$try->result;

=example-2 result

use routines;

my $try = Data::Object::Try->new;

$try->call(fun (@args) {

  return [@args];
});

$try->result(1..5);

cpanm Data::Object::Try

perl -MCPAN -e shell
install Data::Object::Try