X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FTry%2FTiny.pm;h=cf8f1f727898b2f39248419adfc4a6ba49e01301;hb=8447a3bf0e1b88bdd07fa584d83c81c64ad192cf;hp=91307b465bd7105d4fae21814641b9df89224293;hpb=79039ae433128d824ddf3d930909434f9fe645d3;p=p5sagit%2FTry-Tiny.git

diff --git a/lib/Try/Tiny.pm b/lib/Try/Tiny.pm
index 91307b4..cf8f1f7 100644
--- a/lib/Try/Tiny.pm
+++ b/lib/Try/Tiny.pm
@@ -2,6 +2,8 @@ package Try::Tiny;
 use 5.006;
 # ABSTRACT: minimal try/catch with proper preservation of $@
 
+our $VERSION = '0.25';
+
 use strict;
 use warnings;
 
@@ -11,7 +13,23 @@ our @EXPORT = our @EXPORT_OK = qw(try catch finally);
 use Carp;
 $Carp::Internal{+__PACKAGE__}++;
 
-BEGIN { eval "use Sub::Name; 1" or *{subname} = sub {1} }
+BEGIN {
+  my $su = $INC{'Sub/Util.pm'} && defined &Sub::Util::set_subname;
+  my $sn = $INC{'Sub/Name.pm'} && eval { Sub::Name->VERSION(0.08) };
+  unless ($su || $sn) {
+    $su = eval { require Sub::Util; } && defined &Sub::Util::set_subname;
+    unless ($su) {
+      $sn = eval { require Sub::Name; Sub::Name->VERSION(0.08) };
+    }
+  }
+
+  *_subname = $su ? \&Sub::Util::set_subname
+            : $sn ? \&Sub::Name::subname
+            : sub { $_[1] };
+  *_HAS_SUBNAME = ($su || $sn) ? sub(){1} : sub(){0};
+}
+
+my @_finally_guards;
 
 # Need to prototype as @ not $$ because of the way Perl evaluates the prototype.
 # Keeping it at $$ means you only ever get 1 sub because we need to eval in a list
@@ -53,9 +71,17 @@ sub try (&;@) {
 
   # name the blocks if we have Sub::Name installed
   my $caller = caller;
-  subname("${caller}::try {...} " => $try);
-  subname("${caller}::catch {...} " => $catch) if $catch;
-  subname("${caller}::finally {...} " => $_) foreach @finally;
+  _subname("${caller}::try {...} " => $try)
+    if _HAS_SUBNAME;
+
+  # set up scope guards to invoke the finally blocks at the end.
+  # this should really be a function scope lexical variable instead of
+  # file scope + local but that causes issues with perls < 5.20 due to
+  # perl rt#119311
+  local $_finally_guards[0] = [
+    map { Try::Tiny::ScopeGuard->_new($_) }
+    @finally
+  ];
 
   # save the value of $@ so we can set $@ back to it in the beginning of the eval
   # and restore $@ after the eval finishes
@@ -77,21 +103,19 @@ sub try (&;@) {
       $try->();
     };
 
-    return 1; # properly set $fail to false
+    return 1; # properly set $failed to false
   };
 
   # preserve the current error and reset the original value of $@
   $error = $@;
   $@ = $prev_error;
 
-  # set up a scope guard to invoke the finally block at the end
-  my @guards =
-    map { Try::Tiny::ScopeGuard->_new($_, $failed ? $error : ()) }
-    @finally;
-
   # at this point $failed contains a true value if the eval died, even if some
   # destructor overwrote $@ as the eval was unwinding.
   if ( $failed ) {
+    # pass $error to the finally blocks
+    push @$_, $error for @{$_finally_guards[0]};
+
     # if we got an error, invoke the catch block.
     if ( $catch ) {
       # This works like given($error), but is backwards compatible and
@@ -116,6 +140,9 @@ sub catch (&;@) {
 
   croak 'Useless bare catch()' unless wantarray;
 
+  my $caller = caller;
+  _subname("${caller}::catch {...} " => $block)
+    if _HAS_SUBNAME;
   return (
     bless(\$block, 'Try::Tiny::Catch'),
     @rest,
@@ -127,6 +154,9 @@ sub finally (&;@) {
 
   croak 'Useless bare finally()' unless wantarray;
 
+  my $caller = caller;
+  _subname("${caller}::finally {...} " => $block)
+    if _HAS_SUBNAME;
   return (
     bless(\$block, 'Try::Tiny::Finally'),
     @rest,
@@ -217,8 +247,8 @@ context or the empty list in list context. The following examples all
 assign C<"bar"> to C<$x>:
 
   my $x = try { die "foo" } catch { "bar" };
-  my $x = try { die "foo" } || { "bar" };
-  my $x = (try { die "foo" }) // { "bar" };
+  my $x = try { die "foo" } || "bar";
+  my $x = (try { die "foo" }) // "bar";
 
   my $x = eval { die "foo" } || "bar";
 
@@ -443,6 +473,8 @@ value.
 
 Using Perl 5.10 you can use L<perlsyn/"Switch statements">.
 
+=for stopwords topicalizer
+
 The C<catch> block is invoked in a topicalizer context (like a C<given> block),
 but note that you can't return a useful value from C<catch> using the C<when>
 blocks without an explicit C<return>.
@@ -464,7 +496,7 @@ concisely match errors:
 =item *
 
 C<@_> is not available within the C<try> block, so you need to copy your
-arglist. In case you want to work with argument values directly via C<@_>
+argument list. In case you want to work with argument values directly via C<@_>
 aliasing (i.e. allow C<$_[1] = "foo">), you need to pass C<@_> by reference:
 
   sub foo {
@@ -532,11 +564,13 @@ C<try> introduces another caller stack frame. L<Sub::Uplevel> is not used. L<Car
 will not report this when using full stack traces, though, because
 C<%Carp::Internal> is used. This lack of magic is considered a feature.
 
+=for stopwords unhygienically
+
 =item *
 
 The value of C<$_> in the C<catch> block is not guaranteed to be the value of
 the exception thrown (C<$@>) in the C<try> block.  There is no safe way to
-ensure this, since C<eval> may be used unhygenically in destructors.  The only
+ensure this, since C<eval> may be used unhygienically in destructors.  The only
 guarantee is that the C<catch> will be called if an exception is thrown.
 
 =item *
@@ -584,7 +618,7 @@ confusing behavior:
 
 Note that this behavior was changed once again in L<Perl5 version 18
 |https://metacpan.org/module/perldelta#given-now-aliases-the-global-_>.
-However, since the entirety of lexical C<$_> is now L<considired experimental
+However, since the entirety of lexical C<$_> is now L<considered experimental
 |https://metacpan.org/module/perldelta#Lexical-_-is-now-experimental>, it
 is unclear whether the new version 18 behavior is final.