Introduce set_temp(), the non-lvalue variant of temp()

[perl/modules/Variable-Temp.git] / lib / Variable / Temp.pm

diff --git a/lib/Variable/Temp.pm b/lib/Variable/Temp.pm
index 8d307cd18d476e9145a1d46c097af8150d807b34..be72888ace01d7b421b3e291464b175232961c1a 100644 (file)
--- a/lib/Variable/Temp.pm
+++ b/lib/Variable/Temp.pm
@@ -53,7 +53,10 @@ Any subsequent assignments to C<$var> in the current (or any inferior) scope wil
 Several C<temp> calls can be made onto the same variable, and the restore are processed in reverse order.
 
 Note that destructors associated with C<$var> will B<not> be called when C<temp> sets the temporary value, but only at the natural end of life of the variable (i.e. at the end of the scope).
-They will trigger after any destructor associated with the replacement C<$var>.
+They will trigger after any destructor associated with the replacement C<$value>.
+
+Due to a shortcoming in the handling of the C<\$> prototype, which was addressed in C<perl> 5.14, the pseudo-statement C<temp $var = $value> will cause compilation errors on C<perl> 5.12.x and below.
+If you want your code to run on these versions of C<perl>, you are encouraged to use L</set_temp> instead.
 
 =cut
 
@@ -64,9 +67,26 @@ sub temp (\$) :lvalue {
  $$var;
 }
 
+=head2 C<set_temp>
+
+    set_temp $var;
+    set_temp $var => $value;
+
+A non-lvalue variant of L</temp> that can be used with any version of C<perl>.
+
+=cut
+
+sub set_temp (\$;$) {
+ my $var  = $_[0];
+ my $save = $$var;
+ &Scope::Upper::reap(sub { $$var = $save } => Scope::Upper::UP);
+ $$var = $_[1] if @_ >= 2;
+ return;
+}
+
 =head1 EXPORT
 
-The function L</temp> is only exported on request by passing C<'temp'> to the module import list.
+The functions L</temp> and L</set_temp> are only exported on request by specifying their names in the module import list.
 
 =cut
 
@@ -74,7 +94,7 @@ use base 'Exporter';
 
 our @EXPORT      = ();
 our %EXPORT_TAGS = ();
-our @EXPORT_OK   = 'temp';
+our @EXPORT_OK   = qw<temp set_temp>;
 
 =head1 CAVEATS