{ "content": [ { "type": "text", "text": "# charnames (perldoc)\n\n## NAME\n\ncharnames - access to Unicode character names and named character sequences; also define character names\n\n## SYNOPSIS\n\nuse charnames ':full';\nprint \"\\N{GREEK SMALL LETTER SIGMA} is called sigma.\\n\";\nprint \"\\N{LATIN CAPITAL LETTER E WITH VERTICAL LINE BELOW}\",\n\" is an officially named sequence of two Unicode characters\\n\";\nuse charnames ':loose';\nprint \"\\N{Greek small-letter sigma}\",\n\"can be used to ignore case, underscores, most blanks,\"\n\"and when you aren't sure if the official name has hyphens\\n\";\nuse charnames ':short';\nprint \"\\N{greek:Sigma} is an upper-case sigma.\\n\";\nuse charnames qw(cyrillic greek);\nprint \"\\N{sigma} is Greek sigma, and \\N{be} is Cyrillic b.\\n\";\nuse utf8;\nuse charnames \":full\", \":alias\" => {\neACUTE => \"LATIN SMALL LETTER E WITH ACUTE\",\nmychar => 0xE8000, # Private use area\n\"自転車に乗る人\" => \"BICYCLIST\"\n};\nprint \"\\N{eACUTE} is a small letter e with an acute.\\n\";\nprint \"\\N{mychar} allows me to name private use characters.\\n\";\nprint \"And I can create synonyms in other languages,\",\n\" such as \\N{自転車に乗る人} for \"BICYCLIST (U+1F6B4)\\n\";\nuse charnames ();\nprint charnames::viacode(0x1234); # prints \"ETHIOPIC SYLLABLE SEE\"\nprintf \"%04X\", charnames::vianame(\"GOTHIC LETTER AHSA\"); # prints\n# \"10330\"\nprint charnames::vianame(\"LATIN CAPITAL LETTER A\"); # prints 65 on\n# ASCII platforms;\n# 193 on EBCDIC\nprint charnames::stringvianame(\"LATIN CAPITAL LETTER A\"); # prints \"A\"\n\n## DESCRIPTION\n\nPragma \"use charnames\" is used to gain access to the names of the Unicode characters and named\ncharacter sequences, and to allow you to define your own character and character sequence names.\n\n## Sections\n\n- **NAME**\n- **SYNOPSIS**\n- **DESCRIPTION**\n- **LOOSE MATCHES**\n- **ALIASES**\n- **CUSTOM ALIASES**\n- **CUSTOM TRANSLATORS**\n- **BUGS** (1 subsections)\n\nUse structuredContent.sections for detailed options, examples, and full documentation.\n" } ], "structuredContent": { "command": "charnames", "section": "", "mode": "perldoc", "summary": "charnames - access to Unicode character names and named character sequences; also define character names", "synopsis": "use charnames ':full';\nprint \"\\N{GREEK SMALL LETTER SIGMA} is called sigma.\\n\";\nprint \"\\N{LATIN CAPITAL LETTER E WITH VERTICAL LINE BELOW}\",\n\" is an officially named sequence of two Unicode characters\\n\";\nuse charnames ':loose';\nprint \"\\N{Greek small-letter sigma}\",\n\"can be used to ignore case, underscores, most blanks,\"\n\"and when you aren't sure if the official name has hyphens\\n\";\nuse charnames ':short';\nprint \"\\N{greek:Sigma} is an upper-case sigma.\\n\";\nuse charnames qw(cyrillic greek);\nprint \"\\N{sigma} is Greek sigma, and \\N{be} is Cyrillic b.\\n\";\nuse utf8;\nuse charnames \":full\", \":alias\" => {\neACUTE => \"LATIN SMALL LETTER E WITH ACUTE\",\nmychar => 0xE8000, # Private use area\n\"自転車に乗る人\" => \"BICYCLIST\"\n};\nprint \"\\N{eACUTE} is a small letter e with an acute.\\n\";\nprint \"\\N{mychar} allows me to name private use characters.\\n\";\nprint \"And I can create synonyms in other languages,\",\n\" such as \\N{自転車に乗る人} for \"BICYCLIST (U+1F6B4)\\n\";\nuse charnames ();\nprint charnames::viacode(0x1234); # prints \"ETHIOPIC SYLLABLE SEE\"\nprintf \"%04X\", charnames::vianame(\"GOTHIC LETTER AHSA\"); # prints\n# \"10330\"\nprint charnames::vianame(\"LATIN CAPITAL LETTER A\"); # prints 65 on\n# ASCII platforms;\n# 193 on EBCDIC\nprint charnames::stringvianame(\"LATIN CAPITAL LETTER A\"); # prints \"A\"", "tldr_summary": null, "tldr_examples": [], "tldr_source": null, "flags": [], "examples": [], "see_also": [], "section_outline": [ { "name": "NAME", "lines": 3, "subsections": [] }, { "name": "SYNOPSIS", "lines": 36, "subsections": [] }, { "name": "DESCRIPTION", "lines": 69, "subsections": [] }, { "name": "LOOSE MATCHES", "lines": 18, "subsections": [] }, { "name": "ALIASES", "lines": 9, "subsections": [] }, { "name": "CUSTOM ALIASES", "lines": 146, "subsections": [] }, { "name": "CUSTOM TRANSLATORS", "lines": 31, "subsections": [] }, { "name": "BUGS", "lines": 1, "subsections": [ { "name": "vianame", "lines": 7 } ] } ], "sections": { "NAME": { "content": "charnames - access to Unicode character names and named character sequences; also define\ncharacter names\n", "subsections": [] }, "SYNOPSIS": { "content": "use charnames ':full';\nprint \"\\N{GREEK SMALL LETTER SIGMA} is called sigma.\\n\";\nprint \"\\N{LATIN CAPITAL LETTER E WITH VERTICAL LINE BELOW}\",\n\" is an officially named sequence of two Unicode characters\\n\";\n\nuse charnames ':loose';\nprint \"\\N{Greek small-letter sigma}\",\n\"can be used to ignore case, underscores, most blanks,\"\n\"and when you aren't sure if the official name has hyphens\\n\";\n\nuse charnames ':short';\nprint \"\\N{greek:Sigma} is an upper-case sigma.\\n\";\n\nuse charnames qw(cyrillic greek);\nprint \"\\N{sigma} is Greek sigma, and \\N{be} is Cyrillic b.\\n\";\n\nuse utf8;\nuse charnames \":full\", \":alias\" => {\neACUTE => \"LATIN SMALL LETTER E WITH ACUTE\",\nmychar => 0xE8000, # Private use area\n\"自転車に乗る人\" => \"BICYCLIST\"\n};\nprint \"\\N{eACUTE} is a small letter e with an acute.\\n\";\nprint \"\\N{mychar} allows me to name private use characters.\\n\";\nprint \"And I can create synonyms in other languages,\",\n\" such as \\N{自転車に乗る人} for \"BICYCLIST (U+1F6B4)\\n\";\n\nuse charnames ();\nprint charnames::viacode(0x1234); # prints \"ETHIOPIC SYLLABLE SEE\"\nprintf \"%04X\", charnames::vianame(\"GOTHIC LETTER AHSA\"); # prints\n# \"10330\"\nprint charnames::vianame(\"LATIN CAPITAL LETTER A\"); # prints 65 on\n# ASCII platforms;\n# 193 on EBCDIC\nprint charnames::stringvianame(\"LATIN CAPITAL LETTER A\"); # prints \"A\"\n", "subsections": [] }, "DESCRIPTION": { "content": "Pragma \"use charnames\" is used to gain access to the names of the Unicode characters and named\ncharacter sequences, and to allow you to define your own character and character sequence names.\n\nAll forms of the pragma enable use of the following 3 functions:\n\n* \"charnames::stringvianame(*name*)\" for run-time lookup of a either a character name or a\nnamed character sequence, returning its string representation\n\n* \"charnames::vianame(*name*)\" for run-time lookup of a character name (but not a named\ncharacter sequence) to get its ordinal value (code point)\n\n* \"charnames::viacode(*code*)\" for run-time lookup of a code point to get its Unicode name.\n\nStarting in Perl v5.16, any occurrence of \"\\N{*CHARNAME*}\" sequences in a double-quotish string\nautomatically loads this module with arguments \":full\" and \":short\" (described below) if it\nhasn't already been loaded with different arguments, in order to compile the named Unicode\ncharacter into position in the string. Prior to v5.16, an explicit \"use charnames\" was required\nto enable this usage. (However, prior to v5.16, the form \"use charnames ();\" did not enable\n\"\\N{*CHARNAME*}\".)\n\nNote that \"\\N{U+*...*}\", where the *...* is a hexadecimal number, also inserts a character into\na string. The character it inserts is the one whose Unicode code point (ordinal value) is equal\nto the number. For example, \"\\N{U+263a}\" is the Unicode (white background, black foreground)\nsmiley face equivalent to \"\\N{WHITE SMILING FACE}\". Also note, \"\\N{*...*}\" can mean a regex\nquantifier instead of a character name, when the *...* is a number (or comma separated pair of\nnumbers (see \"QUANTIFIERS\" in perlreref), and is not related to this pragma.\n\nThe \"charnames\" pragma supports arguments \":full\", \":loose\", \":short\", script names and\ncustomized aliases.\n\nIf \":full\" is present, for expansion of \"\\N{*CHARNAME*}\", the string *CHARNAME* is first looked\nup in the list of standard Unicode character names.\n\n\":loose\" is a variant of \":full\" which allows *CHARNAME* to be less precisely specified. Details\nare in \"LOOSE MATCHES\".\n\nIf \":short\" is present, and *CHARNAME* has the form \"*SCRIPT*:*CNAME*\", then *CNAME* is looked\nup as a letter in script *SCRIPT*, as described in the next paragraph. Or, if \"use charnames\" is\nused with script name arguments, then for \"\\N{*CHARNAME*}\" the name *CHARNAME* is looked up as a\nletter in the given scripts (in the specified order). Customized aliases can override these, and\nare explained in \"CUSTOM ALIASES\".\n\nFor lookup of *CHARNAME* inside a given script *SCRIPTNAME*, this pragma looks in the table of\nstandard Unicode names for the names\n\nSCRIPTNAME CAPITAL LETTER CHARNAME\nSCRIPTNAME SMALL LETTER CHARNAME\nSCRIPTNAME LETTER CHARNAME\n\nIf *CHARNAME* is all lowercase, then the \"CAPITAL\" variant is ignored, otherwise the \"SMALL\"\nvariant is ignored, and both *CHARNAME* and *SCRIPTNAME* are converted to all uppercase for\nlook-up. Other than that, both of them follow loose rules if \":loose\" is also specified; strict\notherwise.\n\nNote that \"\\N{...}\" is compile-time; it's a special form of string constant used inside\ndouble-quotish strings; this means that you cannot use variables inside the \"\\N{...}\". If you\nwant similar run-time functionality, use charnames::stringvianame().\n\nNote, starting in Perl 5.18, the name \"BELL\" refers to the Unicode character U+1F514, instead of\nthe traditional U+0007. For the latter, use \"ALERT\" or \"BEL\".\n\nIt is a syntax error to use \"\\N{NAME}\" where \"NAME\" is unknown.\n\nFor \"\\N{NAME}\", it is a fatal error if \"use bytes\" is in effect and the input name is that of a\ncharacter that won't fit into a byte (i.e., whose ordinal is above 255).\n\nOtherwise, any string that includes a \"\\N{*charname*}\" or \"\\N{U+*code point*}\" will\nautomatically have Unicode rules (see \"Byte and Character Semantics\" in perlunicode).\n", "subsections": [] }, "LOOSE MATCHES": { "content": "By specifying \":loose\", Unicode's loose character name matching\n rules are selected instead of the strict\nexact match used otherwise. That means that *CHARNAME* doesn't have to be so precisely\nspecified. Upper/lower case doesn't matter (except with scripts as mentioned above), nor do any\nunderscores, and the only hyphens that matter are those at the beginning or end of a word in the\nname (with one exception: the hyphen in U+1180 \"HANGUL JUNGSEONG O-E\" does matter). Also, blanks\nnot adjacent to hyphens don't matter. The official Unicode names are quite variable as to where\nthey use hyphens versus spaces to separate word-like units, and this option allows you to not\nhave to care as much. The reason non-medial hyphens matter is because of cases like U+0F60\n\"TIBETAN LETTER -A\" versus U+0F68 \"TIBETAN LETTER A\". The hyphen here is significant, as is the\nspace before it, and so both must be included.\n\n\":loose\" slows down look-ups by a factor of 2 to 3 versus \":full\", but the trade-off may be\nworth it to you. Each individual look-up takes very little time, and the results are cached, so\nthe speed difference would become a factor only in programs that do look-ups of many different\nspellings, and probably only when those look-ups are through \"vianame()\" and \"stringvianame()\",\nsince \"\\N{...}\" look-ups are done at compile time.\n", "subsections": [] }, "ALIASES": { "content": "Starting in Unicode 6.1 and Perl v5.16, Unicode defines many abbreviations and names that were\nformerly Perl extensions, and some additional ones that Perl did not previously accept. The list\nis getting too long to reproduce here, but you can get the complete list from the Unicode web\nsite: .\n\nEarlier versions of Perl accepted almost all the 6.1 names. These were most extensively\ndocumented in the v5.14 version of this pod:\n.\n", "subsections": [] }, "CUSTOM ALIASES": { "content": "You can add customized aliases to standard (\":full\") Unicode naming conventions. The aliases\noverride any standard definitions, so, if you're twisted enough, you can change \"\\N{LATIN\nCAPITAL LETTER A}\" to mean \"B\", etc.\n\nAliases must begin with a character that is alphabetic. After that, each may contain any\ncombination of word (\"\\w\") characters, SPACE (U+0020), HYPHEN-MINUS (U+002D), LEFT PARENTHESIS\n(U+0028), and RIGHT PARENTHESIS (U+0029). These last two should never have been allowed in\nnames, and are retained for backwards compatibility only, and may be deprecated and removed in\nfuture releases of Perl, so don't use them for new names. (More precisely, the first character\nof a name you specify must be something that matches all of \"\\p{IDStart}\", \"\\p{Alphabetic}\",\nand \"\\p{Gc=Letter}\". This makes sure it is what any reasonable person would view as an\nalphabetic character. And, the continuation characters that match \"\\w\" must also match\n\"\\p{IDContinue}\".) Starting with Perl v5.18, any Unicode characters meeting the above criteria\nmay be used; prior to that only Latin1-range characters were acceptable.\n\nAn alias can map to either an official Unicode character name (not a loose matched name) or to a\nnumeric code point (ordinal). The latter is useful for assigning names to code points in Unicode\nprivate use areas such as U+E800 through U+F8FF. A numeric code point must be a non-negative\ninteger, or a string beginning with \"U+\" or \"0x\" with the remainder considered to be a\nhexadecimal integer. A literal numeric constant must be unsigned; it will be interpreted as hex\nif it has a leading zero or contains non-decimal hex digits; otherwise it will be interpreted as\ndecimal. If it begins with \"U+\", it is interpreted as the Unicode code point; otherwise it is\ninterpreted as native. (Only code points below 256 can differ between Unicode and native.) Thus\n\"U+41\" is always the Latin letter \"A\"; but 0x41 can be \"NO-BREAK SPACE\" on EBCDIC platforms.\n\nAliases are added either by the use of anonymous hashes:\n\nuse charnames \":alias\" => {\neACUTE => \"LATIN SMALL LETTER E WITH ACUTE\",\nmychar1 => 0xE8000,\n};\nmy $str = \"\\N{eACUTE}\";\n\nor by using a file containing aliases:\n\nuse charnames \":alias\" => \"pro\";\n\nThis will try to read \"unicore/proalias.pl\" from the @INC path. This file should return a list\nin plain perl:\n\n(\nAGRAVE => \"LATIN CAPITAL LETTER A WITH GRAVE\",\nACIRCUM => \"LATIN CAPITAL LETTER A WITH CIRCUMFLEX\",\nADIAERES => \"LATIN CAPITAL LETTER A WITH DIAERESIS\",\nATILDE => \"LATIN CAPITAL LETTER A WITH TILDE\",\nABREVE => \"LATIN CAPITAL LETTER A WITH BREVE\",\nARING => \"LATIN CAPITAL LETTER A WITH RING ABOVE\",\nAMACRON => \"LATIN CAPITAL LETTER A WITH MACRON\",\nmychar2 => \"U+E8001\",\n);\n\nBoth these methods insert \":full\" automatically as the first argument (if no other argument is\ngiven), and you can give the \":full\" explicitly as well, like\n\nuse charnames \":full\", \":alias\" => \"pro\";\n\n\":loose\" has no effect with these. Input names must match exactly, using \":full\" rules.\n\nAlso, both these methods currently allow only single characters to be named. To name a sequence\nof characters, use a custom translator (described below).\n\ncharnames::stringvianame(*name*)\nThis is a runtime equivalent to \"\\N{...}\". *name* can be any expression that evaluates to a name\naccepted by \"\\N{...}\" under the \":full\" option to \"charnames\". In addition, any other options\nfor the controlling \"use charnames\" in the same scope apply, like \":loose\" or any script list,\n\":short\" option, or custom aliases you may have defined.\n\nThe only differences are due to the fact that \"stringvianame\" is run-time and \"\\N{}\" is compile\ntime. You can't interpolate inside a \"\\N{}\", (so \"\\N{$variable}\" doesn't work); and if the input\nname is unknown, \"stringvianame\" returns \"undef\" instead of it being a syntax error.\n\ncharnames::vianame(*name*)\nThis is similar to \"stringvianame\". The main difference is that under most circumstances,\n\"vianame\" returns an ordinal code point, whereas \"stringvianame\" returns a string. For example,\n\nprintf \"U+%04X\", charnames::vianame(\"FOUR TEARDROP-SPOKED ASTERISK\");\n\nprints \"U+2722\".\n\nThis leads to the other two differences. Since a single code point is returned, the function\ncan't handle named character sequences, as these are composed of multiple characters (it returns\n\"undef\" for these. And, the code point can be that of any character, even ones that aren't legal\nunder the \"use bytes\" pragma,\n\nSee \"BUGS\" for the circumstances in which the behavior differs from that described above.\n\ncharnames::viacode(*code*)\nReturns the full name of the character indicated by the numeric code. For example,\n\nprint charnames::viacode(0x2722);\n\nprints \"FOUR TEARDROP-SPOKED ASTERISK\".\n\nThe name returned is the \"best\" (defined below) official name or alias for the code point, if\navailable; otherwise your custom alias for it, if defined; otherwise \"undef\". This means that\nyour alias will only be returned for code points that don't have an official Unicode name (nor\nalias) such as private use code points.\n\nIf you define more than one name for the code point, it is indeterminate which one will be\nreturned.\n\nAs mentioned, the function returns \"undef\" if no name is known for the code point. In Unicode\nthe proper name for these is the empty string, which \"undef\" stringifies to. (If you ask for a\ncode point past the legal Unicode maximum of U+10FFFF that you haven't assigned an alias to, you\nget \"undef\" plus a warning.)\n\nThe input number must be a non-negative integer, or a string beginning with \"U+\" or \"0x\" with\nthe remainder considered to be a hexadecimal integer. A literal numeric constant must be\nunsigned; it will be interpreted as hex if it has a leading zero or contains non-decimal hex\ndigits; otherwise it will be interpreted as decimal. If it begins with \"U+\", it is interpreted\nas the Unicode code point; otherwise it is interpreted as native. (Only code points below 256\ncan differ between Unicode and native.) Thus \"U+41\" is always the Latin letter \"A\"; but 0x41 can\nbe \"NO-BREAK SPACE\" on EBCDIC platforms.\n\nAs mentioned above under \"ALIASES\", Unicode 6.1 defines extra names (synonyms or aliases) for\nsome code points, most of which were already available as Perl extensions. All these are\naccepted by \"\\N{...}\" and the other functions in this module, but \"viacode\" has to choose which\none name to return for a given input code point, so it returns the \"best\" name. To understand\nhow this works, it is helpful to know more about the Unicode name properties. All code points\nactually have only a single name, which (starting in Unicode 2.0) can never change once a\ncharacter has been assigned to the code point. But mistakes have been made in assigning names,\nfor example sometimes a clerical error was made during the publishing of the Standard which\ncaused words to be misspelled, and there was no way to correct those. The NameAlias property\nwas eventually created to handle these situations. If a name was wrong, a corrected synonym\nwould be published for it, using NameAlias. \"viacode\" will return that corrected synonym as the\n\"best\" name for a code point. (It is even possible, though it hasn't happened yet, that the\ncorrection itself will need to be corrected, and so another NameAlias can be created for that\ncode point; \"viacode\" will return the most recent correction.)\n\nThe Unicode name for each of the control characters (such as LINE FEED) is the empty string.\nHowever almost all had names assigned by other standards, such as the ASCII Standard, or were in\ncommon use. \"viacode\" returns these names as the \"best\" ones available. Unicode 6.1 has created\nNameAliases for each of them, including alternate names, like NEW LINE. \"viacode\" uses the\noriginal name, \"LINE FEED\" in preference to the alternate. Similarly the name returned for\nU+FEFF is \"ZERO WIDTH NO-BREAK SPACE\", not \"BYTE ORDER MARK\".\n\nUntil Unicode 6.1, the 4 control characters U+0080, U+0081, U+0084, and U+0099 did not have\nnames nor aliases. To preserve backwards compatibility, any alias you define for these code\npoints will be returned by this function, in preference to the official name.\n\nSome code points also have abbreviated names, such as \"LF\" or \"NL\". \"viacode\" never returns\nthese.\n\nBecause a name correction may be added in future Unicode releases, the name that \"viacode\"\nreturns may change as a result. This is a rare event, but it does happen.\n", "subsections": [] }, "CUSTOM TRANSLATORS": { "content": "The mechanism of translation of \"\\N{...}\" escapes is general and not hardwired into\ncharnames.pm. A module can install custom translations (inside the scope which \"use\"s the\nmodule) with the following magic incantation:\n\nsub import {\nshift;\n$^H{charnames} = \\&translator;\n}\n\nHere translator() is a subroutine which takes *CHARNAME* as an argument, and returns text to\ninsert into the string instead of the \"\\N{*CHARNAME*}\" escape.\n\nThis is the only way you can create a custom named sequence of code points.\n\nSince the text to insert should be different in \"bytes\" mode and out of it, the function should\ncheck the current state of \"bytes\"-flag as in:\n\nuse bytes (); # for $bytes::hintbits\nsub translator {\nif ($^H & $bytes::hintbits) {\nreturn bytestranslator(@);\n}\nelse {\nreturn utf8translator(@);\n}\n}\n\nSee \"CUSTOM ALIASES\" above for restrictions on *CHARNAME*.\n\nOf course, \"vianame\", \"viacode\", and \"stringvianame\" would need to be overridden as well.\n", "subsections": [] }, "BUGS": { "content": "", "subsections": [ { "name": "vianame", "content": "\"U+...\", it returns a chr instead. In this case, if \"use bytes\" is in effect and the character\nwon't fit into a byte, it returns \"undef\" and raises a warning.\n\nSince evaluation of the translation function (see \"CUSTOM TRANSLATORS\") happens in the middle of\ncompilation (of a string literal), the translation function should not do any \"eval\"s or\n\"require\"s. This restriction should be lifted (but is low priority) in a future version of Perl.\n" } ] } } } }