perl 5.003_05: pod/perlfunc.pod

[perl5.git] / pod / perlref.pod

diff --git a/pod/perlref.pod b/pod/perlref.pod
index d528bc8..53e9f7d 100644 (file)
--- a/pod/perlref.pod
+++ b/pod/perlref.pod
@@ -15,11 +15,15 @@ hashes, hashes of arrays, arrays of hashes of functions, and so on.
 
 Hard references are smart--they keep track of reference counts for you,
 automatically freeing the thing referred to when its reference count
-goes to zero.  If that thing happens to be an object, the object is
+goes to zero.  (Note: The reference counts for values in self-referential
+or cyclic data structures may not go to zero without a little help; see
+L<perlobj/"Two-Phased Garbage Collection"> for a detailed explanation.
+If that thing happens to be an object, the object is
 destructed.  See L<perlobj> for more about objects.  (In a sense,
 everything in Perl is an object, but we usually reserve the word for
 references to objects that have been officially "blessed" into a class package.)
 
+
 A symbolic reference contains the name of a variable, just as a
 symbolic link in the filesystem merely contains the name of a file.  
 The C<*glob> notation is a kind of symbolic reference.  Hard references
@@ -69,8 +73,11 @@ Note that taking a reference to an enumerated list is not the same
 as using square brackets--instead it's the same as creating
 a list of references!
 
-    @list = (\$a, \$b, \$c);  
-    @list = \($a, $b, $c);     # same thing!
+    @list = (\$a, \@b, \%c);  
+    @list = \($a, @b, %c);     # same thing!
+
+As a special case, C<\(@foo)> returns a list of references to the contents 
+of C<@foo>, not a reference to C<@foo> itself.  Likewise for C<%foo>.
 
 =item 3.
 
@@ -207,9 +214,9 @@ are several basic methods.
 
 =item 1.
 
-Anywhere you'd put an identifier as part of a variable or subroutine
-name, you can replace the identifier with a simple scalar variable
-containing a reference of the correct type:
+Anywhere you'd put an identifier (or chain of identifiers) as part
+of a variable or subroutine name, you can replace the identifier with
+a simple scalar variable containing a reference of the correct type:
 
     $bar = $$scalarref;
     push(@$arrayref, $filename);
@@ -230,10 +237,10 @@ However, a "simple scalar" includes an identifier that itself uses method
 
 =item 2.
 
-Anywhere you'd put an identifier as part of a variable or subroutine
-name, you can replace the identifier with a BLOCK returning a reference
-of the correct type.  In other words, the previous examples could be
-written like this:
+Anywhere you'd put an identifier (or chain of identifiers) as part of a
+variable or subroutine name, you can replace the identifier with a
+BLOCK returning a reference of the correct type.  In other words, the
+previous examples could be written like this:
 
     $bar = ${$scalarref};
     push(@{$arrayref}, $filename);