Handle PERLIO= and document a bit.

[p5sagit/p5-mst-13.2.git] / lib / overload.pm

diff --git a/lib/overload.pm b/lib/overload.pm
index 838c91f..81c8598 100644 (file)
--- a/lib/overload.pm
+++ b/lib/overload.pm
@@ -2,7 +2,7 @@ package overload;
 
 our $VERSION = '1.00';
 
-$overload::hint_bits = 0x20000;
+$overload::hint_bits = 0x20000; # HINT_LOCALIZE_HH
 
 sub nil {}
 
@@ -91,7 +91,7 @@ sub AddrRef {
 }
 
 sub StrVal {
-  (OverloadedStringify($_[0]) or ref($_[0]) eq 'Regexp') ?
+  (ref $_[0] && OverloadedStringify($_[0]) or ref($_[0]) eq 'Regexp') ?
     (AddrRef(shift)) :
     "$_[0]";
 }
@@ -108,11 +108,11 @@ sub mycan {                               # Real can would leave stubs.
 }
 
 %constants = (
-             'integer'   =>  0x1000,
-             'float'     =>  0x2000,
-             'binary'    =>  0x4000,
-             'q'         =>  0x8000,
-             'qr'        => 0x10000,
+             'integer'   =>  0x1000, # HINT_NEW_INTEGER
+             'float'     =>  0x2000, # HINT_NEW_FLOAT
+             'binary'    =>  0x4000, # HINT_NEW_BINARY
+             'q'         =>  0x8000, # HINT_NEW_STRING
+             'qr'        => 0x10000, # HINT_NEW_RE
             );
 
 %ops = ( with_assign     => "+ - * / % ** << >> x .",
@@ -333,9 +333,9 @@ The following symbols can be specified in C<use overload> directive:
     "**", "**=", "<<", "<<=", ">>", ">>=", "x", "x=", ".", ".=",
 
 For these operations a substituted non-assignment variant can be called if
-the assignment variant is not available.  Methods for operations "C<+>",
-"C<->", "C<+=>", and "C<-=>" can be called to automatically generate
-increment and decrement methods.  The operation "C<->" can be used to
+the assignment variant is not available.  Methods for operations C<+>,
+C<->, C<+=>, and C<-=> can be called to automatically generate
+increment and decrement methods.  The operation C<-> can be used to
 autogenerate missing methods for unary minus or C<abs>.
 
 See L<"MAGIC AUTOGENERATION">, L<"Calling Conventions for Mutators"> and
@@ -355,10 +355,10 @@ arrays, C<cmp> is used to compare values subject to C<use overload>.
 
     "&", "^", "|", "neg", "!", "~",
 
-"C<neg>" stands for unary minus.  If the method for C<neg> is not
+C<neg> stands for unary minus.  If the method for C<neg> is not
 specified, it can be autogenerated using the method for
-subtraction. If the method for "C<!>" is not specified, it can be
-autogenerated using the methods for "C<bool>", or "C<\"\">", or "C<0+>".
+subtraction. If the method for C<!> is not specified, it can be
+autogenerated using the methods for C<bool>, or C<"">, or C<0+>.
 
 =item * I<Increment and decrement>
 
@@ -382,11 +382,11 @@ C<0+>.
 
 =item * I<Boolean, string and numeric conversion>
 
-    "bool", "\"\"", "0+",
+    'bool', '""', '0+',
 
 If one or two of these operations are not overloaded, the remaining ones can
 be used instead.  C<bool> is used in the flow control operators
-(like C<while>) and for the ternary "C<?:>" operation.  These functions can
+(like C<while>) and for the ternary C<?:> operation.  These functions can
 return any arbitrary Perl value.  If the corresponding operation for this value
 is overloaded too, that operation will be called again with this value.
 
@@ -404,6 +404,9 @@ glob (which may require a stringification).  The same overloading
 happens both for the I<read-filehandle> syntax C<E<lt>$varE<gt>> and
 I<globbing> syntax C<E<lt>${var}E<gt>>.
 
+B<BUGS> Even in list context, the iterator is currently called only
+once and with scalar context.
+
 =item * I<Dereferencing>
 
     '${}', '@{}', '%{}', '&{}', '*{}'.
@@ -919,10 +922,7 @@ numeric value.)  This prints:
 =head2 Two-face references
 
 Suppose you want to create an object which is accessible as both an
-array reference and a hash reference, similar to the
-L<pseudo-hash|perlref/"Pseudo-hashes: Using an array as a hash">
-builtin Perl type.  Let's make it better than a pseudo-hash by
-allowing index 0 to be treated as a normal element.
+array reference and a hash reference.
 
   package two_refs;
   use overload '%{}' => \&gethash, '@{}' => sub { $ {shift()} };