switches, followed by the default Perl library, probably
F</usr/local/lib/perl>, followed by ".", to represent the current
directory. ("." will not be appended if taint checks are enabled,
-either by C<-T> or by C<-t>.) If you need to modify this at runtime,
-you should use the C<use lib> pragma to get the machine-dependent
-library properly loaded also:
+either by C<-T> or by C<-t>, or if configured not to do so by the
+C<-Ddefault_inc_excludes_dot> compile time option.) If you need to
+modify this at runtime, you should use the C<use lib> pragma to get
+the machine-dependent library properly loaded also:
use lib '/mypath/libdir/';
use SomeMod;
Mnemonic: value of B<-i> switch.
+=item @ISA
+X<@ISA>
+
+Each package contains a special array called C<@ISA> which contains a list
+of that class's parent classes, if any. This array is simply a list of
+scalars, each of which is a string that corresponds to a package name. The
+array is examined when Perl does method resolution, which is covered in
+L<perlobj>.
+
+To load packages while adding them to C<@ISA>, see the L<parent> pragma. The
+discouraged L<base> pragma does this as well, but should not be used except
+when compatibility with the discouraged L<fields> pragma is required.
+
=item $^M
X<$^M>
the call, so that you can die from a C<__DIE__> handler. Similarly
for C<__WARN__>.
-Due to an implementation glitch, the C<$SIG{__DIE__}> hook is called
-even inside an C<eval()>. Do not use this to rewrite a pending
-exception in C<$@>, or as a bizarre substitute for overriding
-C<CORE::GLOBAL::die()>. This strange action at a distance may be fixed
-in a future release so that C<$SIG{__DIE__}> is only called if your
-program is about to exit, as was the original intent. Any other use is
-deprecated.
+The C<$SIG{__DIE__}> hook is called even inside an C<eval()>. It was
+never intended to happen this way, but an implementation glitch made
+this possible. This used to be deprecated, as it allowed strange action
+at a distance like rewriting a pending exception in C<$@>. Plans to
+rectify this have been scrapped, as users found that rewriting a
+pending exception is actually a useful feature, and not a bug.
C<__DIE__>/C<__WARN__> handlers are very special in one respect: they
may be called to report (probable) errors found by the parser. In such
See the documentation of C<use VERSION> and C<require VERSION>
for a convenient way to fail if the running Perl interpreter is too old.
-See also C<$]> for a decimal representation of the Perl version.
+See also C<L</$]>> for a decimal representation of the Perl version.
The main advantage of C<$^V> over C<$]> is that, for Perl v5.10.0 or
later, it overloads operators, allowing easy comparison against other
version representations (e.g. decimal, literal v-string, "v1.2.3", or
objects). The disadvantage is that prior to v5.10.0, it was only a
-literal v-string, which can't be easily printed or compared.
+literal v-string, which can't be easily printed or compared, whereas
+the behavior of C<$]> is unchanged on all versions of Perl.
Mnemonic: use ^V for a version object.
=over 8
=item $<I<digits>> ($1, $2, ...)
-X<$1> X<$2> X<$3>
+X<$1> X<$2> X<$3> X<$I<digits>>
Contains the subpattern from the corresponding set of capturing
parentheses from the last successful pattern match, not counting patterns
matched in nested blocks that have been exited already.
+Note there is a distinction between a capture buffer which matches
+the empty string a capture buffer which is optional. Eg, C<(x?)> and
+C<(x)?> The latter may be undef, the former not.
+
These variables are read-only and dynamically-scoped.
Mnemonic: like \digits.
+=item @{^CAPTURE}
+X<@{^CAPTURE}> X<@^CAPTURE>
+
+An array which exposes the contents of the capture buffers, if any, of
+the last successful pattern match, not counting patterns matched
+in nested blocks that have been exited already.
+
+Note that the 0 index of @{^CAPTURE} is equivalent to $1, the 1 index
+is equivalent to $2, etc.
+
+ if ("foal"=~/(.)(.)(.)(.)/) {
+ print join "-", @{^CAPTURE};
+ }
+
+should output "f-o-a-l".
+
+See also L</$I<digits>>, L</%{^CAPTURE}> and L</%{^CAPTURE_ALL}>.
+
+Note that unlike most other regex magic variables there is no single
+letter equivalent to C<@{^CAPTURE}>.
+
+This variable was added in 5.25.7
+
=item $MATCH
=item $&
This variable was added in Perl v5.6.0.
+=item %{^CAPTURE}
+
=item %LAST_PAREN_MATCH
=item %+
-X<%+> X<%LAST_PAREN_MATCH>
+X<%+> X<%LAST_PAREN_MATCH> X<%{^CAPTURE}>
Similar to C<@+>, the C<%+> hash allows access to the named capture
buffers, should they exist, in the last successful match in the
The keys of the C<%+> hash list only the names of buffers that have
captured (and that are thus associated to defined values).
+If multiple distinct capture groups have the same name, then
+C<$+{NAME}> will refer to the leftmost defined group in the match.
+
The underlying behaviour of C<%+> is provided by the
L<Tie::Hash::NamedCapture> module.
Likewise, if the last successful match changes, then the results may be
surprising.
-This variable was added in Perl v5.10.0.
+This variable was added in Perl v5.10.0. The C<%{^CAPTURE}> alias was
+added in 5.25.7.
This variable is read-only and dynamically-scoped.
This variable was added in Perl v5.6.0.
+=item %{^CAPTURE_ALL}
+X<%{^CAPTURE_ALL}>
+
=item %-
X<%->
Likewise, if the last successful match changes, then the results may be
surprising.
-This variable was added in Perl v5.10.0.
+This variable was added in Perl v5.10.0. The C<%{^CAPTURE_ALL}> alias was
+added in 5.25.7.
This variable is read-only and dynamically-scoped.
function.
This variable was added in Perl 5.8.2 and removed in 5.26.0.
+Setting it to anything other than C<undef> was made fatal in Perl 5.28.0.
=item ${^GLOBAL_PHASE}
X<${^GLOBAL_PHASE}>
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