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  try { die 'foo' } finally { $x = 'bar' };
  try { die 'foo' } catch { warn "Got a die: $_" } finally { $x = 'bar' };

C<finally> blocks are always executed making them suitable for cleanup code
which cannot be handled using local.  You can add as many C<finally> blocks to a
given C<try> block as you like.

Note that adding a C<finally> block without a preceding C<catch> block
suppresses any errors. This behaviour is consistent with using a standalone
C<eval>, but it is not consistent with C<try>/C<finally> patterns found in
other programming languages, such as Java, Python, Javascript or C#. If you
learned the C<try>/C<finally> pattern from one of these languages, watch out for
this.

=head1 EXPORTS

All functions are exported by default using L<Exporter>.

If you need to rename the C<try>, C<catch> or C<finally> keyword consider using
L<Sub::Import> to get L<Sub::Exporter>'s flexibility.

=over 4

=item try (&;@)

Takes one mandatory C<try> subroutine, an optional C<catch> subroutine and C<finally>
subroutine.

The mandatory subroutine is evaluated in the context of an C<eval> block.

If no error occurred the value from the first block is returned, preserving
list/scalar context.

If there was an error and the second subroutine was given it will be invoked
with the error in C<$_> (localized) and as that block's first and only
argument.

C<$@> does B<not> contain the error. Inside the C<catch> block it has the same
value it had before the C<try> block was executed.

Note that the error may be false, but if that happens the C<catch> block will
still be invoked.

Once all execution is finished then the C<finally> block, if given, will execute.

=item catch (&;@)

Intended to be used in the second argument position of C<try>.

Returns a reference to the subroutine it was given but blessed as
C<Try::Tiny::Catch> which allows try to decode correctly what to do
with this code reference.

  catch { ... }

Inside the C<catch> block the caught error is stored in C<$_>, while previous
value of C<$@> is still available for use.  This value may or may not be
meaningful depending on what happened before the C<try>, but it might be a good
idea to preserve it in an error stack.

For code that captures C<$@> when throwing new errors (i.e.
L<Class::Throwable>), you'll need to do:

  local $@ = $_;

=item finally (&;@)

  try     { ... }
  catch   { ... }
  finally { ... };

Or

  try     { ... }
  finally { ... };

Or even

  try     { ... }
  finally { ... }
  catch   { ... };

Intended to be the second or third element of C<try>. C<finally> blocks are always
executed in the event of a successful C<try> or if C<catch> is run. This allows
you to locate cleanup code which cannot be done via C<local()> e.g. closing a file
handle.

When invoked, the C<finally> block is passed the error that was caught.  If no
error was caught, it is passed nothing.  (Note that the C<finally> block does not
localize C<$_> with the error, since unlike in a C<catch> block, there is no way
to know if C<$_ == undef> implies that there were no errors.) In other words,
the following code does just what you would expect:

  try {
    die_sometimes();
  } catch {
    # ...code run in case of error
  } finally {
    if (@_) {
      print "The try block died with: @_\n";
    } else {
      print "The try block ran without error.\n";
    }
  };

B<You must always do your own error handling in the C<finally> block>. C<Try::Tiny> will
not do anything about handling possible errors coming from code located in these
blocks.

Furthermore B<exceptions in C<finally> blocks are not trappable and are unable
to influence the execution of your program>. This is due to limitation of
C<DESTROY>-based scope guards, which C<finally> is implemented on top of. This
may change in a future version of Try::Tiny.

In the same way C<catch()> blesses the code reference this subroutine does the same
except it bless them as C<Try::Tiny::Finally>.

=back

=head1 BACKGROUND