For example you cannot force little-endianness on a type that
is inside a big-endian group.
-=item Can't use keyword '%s' as a label
-
-(F) You attempted to use a reserved keyword, such as C<print> or C<BEGIN>,
-as a statement label. This is disallowed since Perl 5.11.0.
-
=item Can't use "my %s" in sort comparison
(F) The global variables $a and $b are reserved for sort comparisons.
long for Perl to handle. You have to be seriously twisted to write code
that triggers this error.
+=item Deprecated character(s) in \\N{...} starting at '%s'
+
+(D deprecated) Just about anything is legal for the C<...> in C<\N{...}>.
+But starting in 5.12, non-reasonable ones that don't look like names are
+deprecated. A reasonable name begins with an alphabetic character and
+continues with any combination of alphanumerics, dashes, spaces, parentheses or
+colons.
+
=item Deprecated use of my() in false conditional
(D deprecated) You used a declaration similar to C<my $x if 0>.
=item (Did you mean &%s instead?)
-(W) You probably referred to an imported subroutine &FOO as $FOO or some
-such.
+(W misc) You probably referred to an imported subroutine &FOO as $FOO or
+some such.
=item (Did you mean "local" instead of "our"?)
names (like C<$A::B>). You've exceeded Perl's limits. Future versions
of Perl are likely to eliminate these arbitrary limitations.
-=item Ignoring zero length \N{} in character class"
+=item Ignoring zero length \N{} in character class
(W) Named Unicode character escapes (\N{...}) may return a
zero length sequence. When such an escape is used in a character class
=item Missing braces on \N{}
(F) Wrong syntax of character name literal C<\N{charname}> within
-double-quotish context.
+double-quotish context. This can also happen when there is a space (or
+comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
+This modifier does not change the requirement that the brace immediately follow
+the C<\N>.
=item Missing comma after first argument to %s function
(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
-=item Missing right brace on \\N{} or unescaped left brace after \\N. Assuming the latter
+=item Missing right brace on \\N{} or unescaped left brace after \\N
+
+(F)
+C<\N> has two meanings.
-(W syntax)
-C<\N> has traditionally been followed by a name enclosed in braces,
-meaning the character (or sequence of characters) given by that name.
+The traditional one has it followed by a name enclosed
+in braces, meaning the character (or sequence of characters) given by that name.
Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
-double-quoted strings and regular expression patterns.
-In patterns, it doesn't have the meaning an unescaped C<*> does.
+double-quoted strings and regular expression patterns. In patterns, it doesn't
+have the meaning an unescaped C<*> does.
-Starting in Perl 5.12.0, C<\N> also can have an additional meaning in patterns,
-namely to match a non-newline character. (This is like C<.> but is not
-affected by the C</s> modifier.)
+Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only) in
+patterns, namely to match a non-newline character. (This is short for
+C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
This can lead to some ambiguities. When C<\N> is not followed immediately by a
-left brace, Perl assumes the "match non-newline character" meaning. Also, if
+left brace, Perl assumes the C<[^\n]> meaning. Also, if
the braces form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes
that this means to match the given quantity of non-newlines (in these examples,
-3, and 5 or more, respectively). In all other case, where there is a C<\N{>
+3; and 5 or more, respectively). In all other case, where there is a C<\N{>
and a matching C<}>, Perl assumes that a character name is desired.
However, if there is no matching C<}>, Perl doesn't know if it was mistakenly
-omitted, or if "match non-newline" followed by "match a C<{>" was desired.
-It assumes the latter because that is actually a valid interpretation as
-written, unlike the other case. If you meant the former, you need to add the
-matching right brace. If you did mean the latter, you can silence this warning
-by writing instead C<\N\{>.
+omitted, or if C<[^\n]{> was desired, and
+raises this error. If you meant the former, add the right brace; if you meant
+the latter, escape the brace with a backslash, like so: C<\N\{>
=item Missing right curly or square bracket
=item \\N in a character class must be a named character: \\N{...}
-The new (5.12) meaning of C<\N> to match non-newlines is not valid in a
-bracketed character class, for the same reason that C<.> in a character class
-loses its specialness: it matches almost everything, which is probably not what
-you want.
+(F) The new (5.12) meaning of C<\N> as C<[^\n]> is not valid in a bracketed
+character class, for the same reason that C<.> in a character class loses its
+specialness: it matches almost everything, which is probably not what you want.
+
+=item \\N{NAME} must be resolved by the lexer
+
+(F) When compiling a regex pattern, an unresolved named character or sequence
+was encountered. This can happen in any of several ways that bypass the lexer,
+such as using single-quotish context, or an extra backslash in double quotish:
+
+ $re = '\N{SPACE}'; # Wrong!
+ $re = "\\N{SPACE}"; # Wrong!
+ /$re/;
+
+Instead, use double-quotes with a single backslash:
+
+ $re = "\N{SPACE}"; # ok
+ /$re/;
+
+The lexer can be bypassed as well by creating the pattern from smaller
+components:
+
+ $re = '\N';
+ /${re}{SPACE}/; # Wrong!
+
+It's not a good idea to split a construct in the middle like this, and it
+doesn't work here. Instead use the solution above.
+
+Finally, the message also can happen under the C</x> regex modifier when the
+C<\N> is separated by spaces from the C<{>, in which case, remove the spaces.
+
+ /\N {SPACE}/x; # Wrong!
+ /\N{SPACE}/x; # ok
=item Name "%s::%s" used only once: possible typo
=item Invalid hexadecimal number in \\N{U+...}
(F) The character constant represented by C<...> is not a valid hexadecimal
-number.
+number. Either it is empty, or you tried to use a character other than 0 - 9
+or A - F, a - f in a hexadecimal number.
=item Negative '/' count in unpack
use the /g modifier. Currently, /c is meaningful only when /g is
used. (This may change in the future.)
+=item Use of := for an empty attribute list is deprecated
+
+(D deprecated) The construction C<my $x := 42> currently
+parses correctly in perl, being equivalent to C<my $x : = 42>
+(applying an empty attribute list to C<$x>). This useless
+construct is now deprecated, so C<:=> can be reclaimed as a new
+operator in the future.
+
=item Use of freed value in iteration
(F) Perhaps you modified the iterated array within the loop?
=item Variable "%s" is not imported%s
-(F) While "use strict" in effect, you referred to a global variable that
-you apparently thought was imported from another module, because
+(W misc) With "use strict" in effect, you referred to a global variable
+that you apparently thought was imported from another module, because
something else of the same name (usually a subroutine) is exported by
that module. It usually means you put the wrong funny character on the
front of your variable.
projects / p5sagit/p5-mst-13.2.git / blobdiff