+The name returned is the "best" (defined below) official name or alias
+for the code point, if
+available; otherwise your custom alias for it, if defined; otherwise C<undef>.
+This means that your alias will only be returned for code points that don't
+have an official Unicode name (nor alias) such as private use code points.
+
+If you define more than one name for the code point, it is indeterminate
+which one will be returned.
+
+As mentioned, the function returns C<undef> if no name is known for the code
+point. In Unicode the proper name for these is the empty string, which
+C<undef> stringifies to. (If you ask for a code point past the legal
+Unicode maximum of U+10FFFF that you haven't assigned an alias to, you
+get C<undef> plus a warning.)
+
+The input number must be a non-negative integer, or a string beginning
+with C<"U+"> or C<"0x"> with the remainder considered to be a
+hexadecimal integer. A literal numeric constant must be unsigned; it
+will be interpreted as hex if it has a leading zero or contains
+non-decimal hex digits; otherwise it will be interpreted as decimal.
+If it begins with C<"U+">, it is interpreted as the Unicode code point;
+otherwise it is interpreted as native. (Only code points below 256 can
+differ between Unicode and native.) Thus C<U+41> is always the Latin letter
+"A"; but C<0x41> can be "NO-BREAK SPACE" on EBCDIC platforms.
+
+As mentioned above under L</ALIASES>, Unicode 6.1 defines extra names
+(synonyms or aliases) for some code points, most of which were already
+available as Perl extensions. All these are accepted by C<\N{...}> and the
+other functions in this module, but C<viacode> has to choose which one
+name to return for a given input code point, so it returns the "best" name.
+To understand how this works, it is helpful to know more about the Unicode
+name properties. All code points actually have only a single name, which
+(starting in Unicode 2.0) can never change once a character has been assigned
+to the code point. But mistakes have been made in assigning names, for
+example sometimes a clerical error was made during the publishing of the
+Standard which caused words to be misspelled, and there was no way to correct
+those. The Name_Alias property was eventually created to handle these
+situations. If a name was wrong, a corrected synonym would be published for
+it, using Name_Alias. C<viacode> will return that corrected synonym as the
+"best" name for a code point. (It is even possible, though it hasn't happened
+yet, that the correction itself will need to be corrected, and so another
+Name_Alias can be created for that code point; C<viacode> will return the
+most recent correction.)
+
+The Unicode name for each of the control characters (such as LINE FEED) is the
+empty string. However almost all had names assigned by other standards, such
+as the ASCII Standard, or were in common use. C<viacode> returns these names
+as the "best" ones available. Unicode 6.1 has created Name_Aliases for each
+of them, including alternate names, like NEW LINE. C<viacode> uses the
+original name, "LINE FEED" in preference to the alternate. Similarly the
+name returned for U+FEFF is "ZERO WIDTH NO-BREAK SPACE", not "BYTE ORDER
+MARK".
+
+Until Unicode 6.1, the 4 control characters U+0080, U+0081, U+0084, and U+0099
+did not have names nor aliases.
+To preserve backwards compatibility, any alias you define for these code
+points will be returned by this function, in preference to the official name.
+
+Some code points also have abbreviated names, such as "LF" or "NL".
+C<viacode> never returns these.
+
+Because a name correction may be added in future Unicode releases, the name
+that C<viacode> returns may change as a result. This is a rare event, but it
+does happen.
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