diff options
| -rw-r--r-- | lib/charnames.pm | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/lib/charnames.pm b/lib/charnames.pm index 020ab7ce61..d758543dea 100644 --- a/lib/charnames.pm +++ b/lib/charnames.pm @@ -987,7 +987,7 @@ charnames - access to Unicode character names and named character sequences; als mychar => 0xE8000, # Private use area }; print "\N{e_ACUTE} is a small letter e with an acute.\n"; - print "\\N{mychar} allows me to name private use characters.\n"; + print "\N{mychar} allows me to name private use characters.\n"; use charnames (); print charnames::viacode(0x1234); # prints "ETHIOPIC SYLLABLE SEE" @@ -1043,26 +1043,29 @@ name, when the I<...> is a number (or comma separated pair of numbers (see L<perlreref/QUANTIFIERS>), and is not related to this pragma. The C<charnames> pragma supports arguments C<:full>, C<:short>, script -names and customized aliases. If C<:full> is present, for expansion of +names and L<customized aliases|/CUSTOM ALIASES>. If C<:full> is present, for +expansion of C<\N{I<CHARNAME>}>, the string I<CHARNAME> is first looked up in the list of standard Unicode character names. If C<:short> is present, and I<CHARNAME> has the form C<I<SCRIPT>:I<CNAME>>, then I<CNAME> is looked up -as a letter in script I<SCRIPT>. If C<use charnames> is used +as a letter in script I<SCRIPT>, as described in the next paragraph. +Or, if C<use charnames> is used with script name arguments, then for C<\N{I<CHARNAME>}> the name I<CHARNAME> is looked up as a letter in the given scripts (in the specified order). Customized aliases can override these, and are explained in L</CUSTOM ALIASES>. For lookup of I<CHARNAME> inside a given script I<SCRIPTNAME> -this pragma looks for the names +this pragma looks in the table of standard Unicode names for the names SCRIPTNAME CAPITAL LETTER CHARNAME SCRIPTNAME SMALL LETTER CHARNAME SCRIPTNAME LETTER CHARNAME -in the table of standard Unicode names. If I<CHARNAME> is lowercase, +If I<CHARNAME> is all lowercase, then the C<CAPITAL> variant is ignored, otherwise the C<SMALL> variant -is ignored. +is ignored, and both I<CHARNAME> and I<SCRIPTNAME> are converted to all +uppercase for look-up. Note that C<\N{...}> is compile-time; it's a special form of string constant used inside double-quotish strings; this means that you cannot @@ -1089,8 +1092,8 @@ L<perlunicode/Byte and Character Semantics>). =head1 ALIASES -A few aliases have been defined for convenience: instead of having -to use the official names +A few aliases have been defined for convenience; instead of having +to use the official names, LINE FEED (LF) FORM FEED (FF) @@ -1245,7 +1248,7 @@ well, like use charnames ":full", ":alias" => "pro"; -Also, both these methods currently allow only a single character to be named. +Also, both these methods currently allow only single characters to be named. To name a sequence of characters, use a L<custom translator|/CUSTOM TRANSLATORS> (described below). @@ -1261,7 +1264,7 @@ prints "FOUR TEARDROP-SPOKED ASTERISK". The name returned is the official name for the code point, if available; otherwise your custom alias for it. This means that your alias will only be returned for code points that don't have an official -Unicode name (nor Unicode version 1 name), such as private use code +Unicode name (nor a Unicode version 1 name), such as private use code points, and the 4 control characters U+0080, U+0081, U+0084, and U+0099. If you define more than one name for the code point, it is indeterminate which one will be returned. @@ -1306,13 +1309,15 @@ prints "U+2722". This leads to the other two differences. Since a single code point is returned, the function can't handle named character sequences, as these are -composed of multiple characters. And, the code point can be that of any +composed of multiple characters (it returns C<undef> for these. And, the code +point can be that of any character, even ones that aren't legal under the C<S<use bytes>> pragma, =head1 CUSTOM TRANSLATORS The mechanism of translation of C<\N{...}> escapes is general and not -hardwired into F<charnames.pm>. A module can install custom +hardwired into F<charnames.pm>. This is the only way you can create +a custom named sequence of code points. A module can install custom translations (inside the scope which C<use>s the module) with the following magic incantation: @@ -1344,7 +1349,7 @@ overridden as well. =head1 BUGS -vianame normally returns an ordinal code point, but when the input name is of +vianame() normally returns an ordinal code point, but when the input name is of the form C<U+...>, it returns a chr instead. In this case, if C<use bytes> is in effect and the character won't fit into a byte, it returns C<undef> and raises a warning. |