array. So C<$1> is C<${^CAPTURE}[0]>. This is a more efficient equivalent
to code like C<substr($matched_string,$-[0],$+[0]-$-[0])>, and you don't
have to keep track of the C<$matched_string> either. This variable has no
-single character equivalent. Note, like the other regex magic variables
-the contents of this variable is dynamic, if you wish to store it beyond
+single character equivalent. Note that, like the other regex magic variables,
+the contents of this variable is dynamic; if you wish to store it beyond
the lifetime of the match you must copy it to another array.
-C<%{^CAPTURE}> is the equivalent to C<%+> (I<i.e.>, named captures). Other than
+C<%{^CAPTURE}> is equivalent to C<%+> (I<i.e.>, named captures). Other than
being more self documenting there is no difference between the two forms.
-C<%{^CAPTURE_ALL}> is the equivalent to C<%-> (I<i.e.>, all named captures).
+C<%{^CAPTURE_ALL}> is equivalent to C<%-> (I<i.e.>, all named captures).
Other than being more self documenting there is no difference between the
two forms.
=head2 C<CORE> subroutines for hash and array functions callable via
reference
-The hash and array functions in the C<CORE> namespace--C<keys>, C<each>,
-C<values>, C<push>, C<pop>, C<shift>, C<unshift> and C<splice>--, can now
+The hash and array functions in the C<CORE> namespace (C<keys>, C<each>,
+C<values>, C<push>, C<pop>, C<shift>, C<unshift> and C<splice>) can now
be called with ampersand syntax (C<&CORE::keys(\%hash>) and via reference
(C<< my $k = \&CORE::keys; $k-E<gt>(\%hash) >>). Previously they could only be
used when inlined.
=back
-=head2 "Escaped" colons and relative paths in PATH
+=head2 Escaped colons and relative paths in PATH
On Unix systems, Perl treats any relative paths in the PATH environment
variable as tainted when starting a new process. Previously, it was
=item *
-Account for possibility of DOS file endings.
+Account for the possibility of DOS file endings.
=back
=item *
-Since v5.18 for testing purposes we have included support for
+Since v5.18 for testing purposes, we have included support for
building perl with a variety of non-standard, and non-recommended
hash functions. Since we do not recommend the use of these functions
we have removed them and their corresponding build options. Specifically
=item *
Several new macros and functions for dealing with Unicode and
-UTF-8-encoded strings have been added to the API, as well some changes in
+UTF-8-encoded strings have been added to the API, as well as some
+changes in
functionality of existing functions (see L<perlapi/Unicode Support> for
more details):
UTF-8 may be syntactically valid, but the code point it represents is
not capable of being represented in the word length on the platform.
What "allowed" means in this case is that the function doesn't return an
-error, and advances the parse pointer to beyond the UTF-8 in question,
-but it returns the Unicode REPLACEMENT CHARACTER as the value of the
-code point (since the real value is not representable).
+error, and it advances the parse pointer to beyond the UTF-8 in
+question, but it returns the Unicode REPLACEMENT CHARACTER as the value
+of the code point (since the real value is not representable).
C<utf8n_to_uvchr> has been changed to not
abandon searching for other malformations when the first one is
C<valid_utf8_to_uvchr()> has been added to the API (although it was
present in core earlier). Like C<utf8_to_uvchr_buf()>, but assumes that
-the next character is well-formed.
+the next character is well-formed. Use with caution.
=item *
=item *
Under C<use utf8>, the entire Perl program is now checked that the UTF-8
-is wellformed. This resolves [perl #126310].
+is wellformed. [perl #126310].
=item *
=item *
-Fixed a comment skipping error under C</x>; it could stop skipping a
-byte early, which could be in the middle of a UTF-8 character.
-[perl #130495].
+Fixed a comment skipping error in patterns under C</x>; it could stop
+skipping a byte early, which could be in the middle of a UTF-8
+character. [perl #130495].
=item *
=item *
-Fix an assertion error which could be triggered when lookahead string
+Fix an assertion error which could be triggered when a lookahead string
in patterns exceeded a minimum length. [perl #130522].
=item *
=item *
-Properly recognize mathematical digit ranges starting at U+1D7E.
C<use re 'strict'> is supposed to warn if you use a range whose start
and end digit aren't from the same group of 10. It didn't do that
for five groups of mathematical digits starting at U+1D7E.
=item *
-A crash in executing a regex with a floating UTF-8 substring against a
+A crash in executing a regex with a non-anchored UTF-8 substring against a
target string that also used UTF-8 has been fixed. [perl #129350]
=item *
Many issues relating to C<printf "%a"> of hexadecimal floating point
were fixed. In addition, the "subnormals" (formerly known as "denormals")
-floating point anumbers are now supported both with the plain IEEE 754
+floating point numbers are now supported both with the plain IEEE 754
floating point numbers (64-bit or 128-bit) and the x86 80-bit
"extended precision". Note that subnormal hexadecimal floating
point literals will give a warning about "exponent underflow".
=item *
Code that looks for a variable name associated with an uninitialized value
-could cause an assertion in cases where magic is involved, such as
+could cause an assertion failure in cases where magic is involved, such as
C<$ISA[0][0]>. This has now been fixed.
L<[perl #128253]|https://rt.perl.org/Public/Bug/Display.html?id=128253>
=item *
Some modules have been broken by the L<context stack rework|/Internal Changes>.
-These modules were relying on non-guaranteed implementation details in perl.
+These modules were relying on non-guaranteed implementation details in
+the perl interpreter.
Their maintainers have been informed, and should contact perl5-porters for
advice if needed. Below is a subset of these modules:
=item * L<Coro>
-L<Coro> and Perl 5.22 were already incompatible due to a change in the perl,
+L<Coro> and Perl 5.22 were already incompatible due to a change in the perl
+interpreter,
and the reworking on the perl context stack creates a further incompatibility.
perl5-porters has L<discussed the issue on the mailing
list|http://www.nntp.perl.org/group/perl.perl5.porters/2016/05/msg236174.html>.
https://perl5.git.perl.org / perl5.git / commitdiff