Determination of Character Unicode Blocks

WJG (12/12/16) Much of the data I deal with comes in a mixture of languages or rather, scripts. When strings of that data are being parsed its useful to known what script is being examined so substrings can be extracted. The way this can be done is by comparing the hex value for each character in a string against a list of block ranges as provided in the Unicode specification. This list, as can be seen by its structure below, has evolved over time. Certain scripts (e.g. Tibetan) are contained in a single contiguous block, whereas Chinese, Japanese and Korean (CJK), occupy both shared and separated blocks.

# !/bin/sh
# the next line restarts using tclsh \
exec tclsh "$0" "$@"

# list of current unicode blocks as found at:
set unicode_blocks "{0000} {007F} {Basic Latin}
{0080} {00FF} {Latin-1 Supplement}
{0100} {017F} {Latin Extended-A}
{0180} {024F} {Latin Extended-B}
{0250} {02AF} {IPA Extensions}
{02B0} {02FF} {Spacing Modifier Letters}
{0300} {036F} {Combining Diacritical Marks}
{0370} {03FF} {Greek and Coptic}
{0400} {04FF} {Cyrillic}
{0500} {052F} {Cyrillic Supplement}
{0530} {058F} {Armenian}
{0590} {05FF} {Hebrew}
{0600} {06FF} {Arabic}
{0700} {074F} {Syriac}
{0750} {077F} {Arabic Supplement}
{0780} {07BF} {Thaana}
{07C0} {07FF} {NKo}
{0800} {083F} {Samaritan}
{0840} {085F} {Mandaic}
{08A0} {08FF} {Arabic Extended-A}
{0900} {097F} {Devanagari}
{0980} {09FF} {Bengali}
{0A00} {0A7F} {Gurmukhi}
{0A80} {0AFF} {Gujarati}
{0B00} {0B7F} {Oriya}
{0B80} {0BFF} {Tamil}
{0C00} {0C7F} {Telugu}
{0C80} {0CFF} {Kannada}
{0D00} {0D7F} {Malayalam}
{0D80} {0DFF} {Sinhala}
{0E00} {0E7F} {Thai}
{0E80} {0EFF} {Lao}
{0F00} {0FFF} {Tibetan}
{1000} {109F} {Myanmar}
{10A0} {10FF} {Georgian}
{1100} {11FF} {Hangul Jamo}
{1200} {137F} {Ethiopic}
{1380} {139F} {Ethiopic Supplement}
{13A0} {13FF} {Cherokee}
{1400} {167F} {Unified Canadian Aboriginal Syllabics}
{1680} {169F} {Ogham}
{16A0} {16FF} {Runic}
{1700} {171F} {Tagalog}
{1720} {173F} {Hanunoo}
{1740} {175F} {Buhid}
{1760} {177F} {Tagbanwa}
{1780} {17FF} {Khmer}
{1800} {18AF} {Mongolian}
{18B0} {18FF} {Unified Canadian Aboriginal Syllabics Extended}
{1900} {194F} {Limbu}
{1950} {197F} {Tai Le}
{1980} {19DF} {New Tai Lue}
{19E0} {19FF} {Khmer Symbols}
{1A00} {1A1F} {Buginese}
{1A20} {1AAF} {Tai Tham}
{1AB0} {1AFF} {Combining Diacritical Marks Extended}
{1B00} {1B7F} {Balinese}
{1B80} {1BBF} {Sundanese}
{1BC0} {1BFF} {Batak}
{1C00} {1C4F} {Lepcha}
{1C50} {1C7F} {Ol Chiki}
{1C80} {1C8F} {Cyrillic Extended-C}
{1CC0} {1CCF} {Sundanese Supplement}
{1CD0} {1CFF} {Vedic Extensions}
{1D00} {1D7F} {Phonetic Extensions}
{1D80} {1DBF} {Phonetic Extensions Supplement}
{1DC0} {1DFF} {Combining Diacritical Marks Supplement}
{1E00} {1EFF} {Latin Extended Additional}
{1F00} {1FFF} {Greek Extended}
{2000} {206F} {General Punctuation}
{2070} {209F} {Superscripts and Subscripts}
{20A0} {20CF} {Currency Symbols}
{20D0} {20FF} {Combining Diacritical Marks for Symbols}
{2100} {214F} {Letterlike Symbols}
{2150} {218F} {Number Forms}
{2190} {21FF} {Arrows}
{2200} {22FF} {Mathematical Operators}
{2300} {23FF} {Miscellaneous Teis_CJKical}
{2400} {243F} {Control Pictures}
{2440} {245F} {Optical Character Recognition}
{2460} {24FF} {Enclosed Alphanumerics}
{2500} {257F} {Box Drawing}
{2580} {259F} {Block Elements}
{25A0} {25FF} {Geometric Shapes}
{2600} {26FF} {Miscellaneous Symbols}
{2700} {27BF} {Dingbats}
{27C0} {27EF} {Miscellaneous Mathematical Symbols-A}
{27F0} {27FF} {Supplemental Arrows-A}
{2800} {28FF} {Braille Patterns}
{2900} {297F} {Supplemental Arrows-B}
{2980} {29FF} {Miscellaneous Mathematical Symbols-B}
{2A00} {2AFF} {Supplemental Mathematical Operators}
{2B00} {2BFF} {Miscellaneous Symbols and Arrows}
{2C00} {2C5F} {Glagolitic}
{2C60} {2C7F} {Latin Extended-C}
{2C80} {2CFF} {Coptic}
{2D00} {2D2F} {Georgian Supplement}
{2D30} {2D7F} {Tifinagh}
{2D80} {2DDF} {Ethiopic Extended}
{2DE0} {2DFF} {Cyrillic Extended-A}
{2E00} {2E7F} {Supplemental Punctuation}
{2E80} {2EFF} {CJK Radicals Supplement}
{2F00} {2FDF} {Kangxi Radicals}
{2FF0} {2FFF} {Ideographic Description Characters}
{3000} {303F} {CJK Symbols and Punctuation}
{3040} {309F} {Hiragana}
{30A0} {30FF} {Katakana}
{3100} {312F} {Bopomofo}
{3130} {318F} {Hangul Compatibility Jamo}
{3190} {319F} {Kanbun}
{31A0} {31BF} {Bopomofo Extended}
{31C0} {31EF} {CJK Strokes}
{31F0} {31FF} {Katakana Phonetic Extensions}
{3200} {32FF} {Enclosed CJK Letters and Months}
{3300} {33FF} {CJK Compatibility}
{3400} {4DBF} {CJK Unified Ideographs Extension A}
{4DC0} {4DFF} {Yijing Hexagram Symbols}
{4E00} {9FFF} {CJK Unified Ideographs}
{A000} {A48F} {Yi Syllables}
{A490} {A4CF} {Yi Radicals}
{A4D0} {A4FF} {Lisu}
{A500} {A63F} {Vai}
{A640} {A69F} {Cyrillic Extended-B}
{A6A0} {A6FF} {Bamum}
{A700} {A71F} {Modifier Tone Letters}
{A720} {A7FF} {Latin Extended-D}
{A800} {A82F} {Syloti Nagri}
{A830} {A83F} {Common Indic Number Forms}
{A840} {A87F} {Phags-pa}
{A880} {A8DF} {Saurashtra}
{A8E0} {A8FF} {Devanagari Extended}
{A900} {A92F} {Kayah Li}
{A930} {A95F} {Rejang}
{A960} {A97F} {Hangul Jamo Extended-A}
{A980} {A9DF} {Javanese}
{A9E0} {A9FF} {Myanmar Extended-B}
{AA00} {AA5F} {Cham}
{AA60} {AA7F} {Myanmar Extended-A}
{AA80} {AADF} {Tai Viet}
{AAE0} {AAFF} {Meetei Mayek Extensions}
{AB00} {AB2F} {Ethiopic Extended-A}
{AB30} {AB6F} {Latin Extended-E}
{AB70} {ABBF} {Cherokee Supplement}
{ABC0} {ABFF} {Meetei Mayek}
{AC00} {D7AF} {Hangul Syllables}
{D7B0} {D7FF} {Hangul Jamo Extended-B}
{D800} {DB7F} {High Surrogates}
{DB80} {DBFF} {High Private Use Surrogates}
{DC00} {DFFF} {Low Surrogates}
{E000} {F8FF} {Private Use Area}
{F900} {FAFF} {CJK Compatibility Ideographs}
{FB00} {FB4F} {Alphabetic Presentation Forms}
{FB50} {FDFF} {Arabic Presentation Forms-A}
{FE00} {FE0F} {Variation Selectors}
{FE10} {FE1F} {Vertical Forms}
{FE20} {FE2F} {Combining Half Marks}
{FE30} {FE4F} {CJK Compatibility Forms}
{FE50} {FE6F} {Small Form Variants}
{FE70} {FEFF} {Arabic Presentation Forms-B}
{FF00} {FFEF} {Halfwidth and Fullwidth Forms}
{FFF0} {FFFF} {Specials}
{10000} {1007F} {Linear B Syllabary}
{10080} {100FF} {Linear B Ideograms}
{10100} {1013F} {Aegean Numbers}
{10140} {1018F} {Ancient Greek Numbers}
{10190} {101CF} {Ancient Symbols}
{101D0} {101FF} {Phaistos Disc}
{10280} {1029F} {Lycian}
{102A0} {102DF} {Carian}
{102E0} {102FF} {Coptic Epact Numbers}
{10300} {1032F} {Old Italic}
{10330} {1034F} {Gothic}
{10350} {1037F} {Old Permic}
{10380} {1039F} {Ugaritic}
{103A0} {103DF} {Old Persian}
{10400} {1044F} {Deseret}
{10450} {1047F} {Shavian}
{10480} {104AF} {Osmanya}
{104B0} {104FF} {Osage}
{10500} {1052F} {Elbasan}
{10530} {1056F} {Caucasian Albanian}
{10600} {1077F} {Linear A}
{10800} {1083F} {Cypriot Syllabary}
{10840} {1085F} {Imperial Aramaic}
{10860} {1087F} {Palmyrene}
{10880} {108AF} {Nabataean}
{108E0} {108FF} {Hatran}
{10900} {1091F} {Phoenician}
{10920} {1093F} {Lydian}
{10980} {1099F} {Meroitic Hieroglyphs}
{109A0} {109FF} {Meroitic Cursive}
{10A00} {10A5F} {Kharoshthi}
{10A60} {10A7F} {Old South Arabian}
{10A80} {10A9F} {Old North Arabian}
{10AC0} {10AFF} {Manichaean}
{10B00} {10B3F} {Avestan}
{10B40} {10B5F} {Inscriptional Parthian}
{10B60} {10B7F} {Inscriptional Pahlavi}
{10B80} {10BAF} {Psalter Pahlavi}
{10C00} {10C4F} {Old Turkic}
{10C80} {10CFF} {Old Hungarian}
{10E60} {10E7F} {Rumi Numeral Symbols}
{11000} {1107F} {Brahmi}
{11080} {110CF} {Kaithi}
{110D0} {110FF} {Sora Sompeng}
{11100} {1114F} {Chakma}
{11150} {1117F} {Mahajani}
{11180} {111DF} {Sharada}
{111E0} {111FF} {Sinhala Archaic Numbers}
{11200} {1124F} {Khojki}
{11280} {112AF} {Multani}
{112B0} {112FF} {Khudawadi}
{11300} {1137F} {Grantha}
{11400} {1147F} {Newa}
{11480} {114DF} {Tirhuta}
{11580} {115FF} {Siddham}
{11600} {1165F} {Modi}
{11660} {1167F} {Mongolian Supplement}
{11680} {116CF} {Takri}
{11700} {1173F} {Ahom}
{118A0} {118FF} {Warang Citi}
{11AC0} {11AFF} {Pau Cin Hau}
{11C00} {11C6F} {Bhaiksuki}
{11C70} {11CBF} {Marchen}
{12000} {123FF} {Cuneiform}
{12400} {1247F} {Cuneiform Numbers and Punctuation}
{12480} {1254F} {Early Dynastic Cuneiform}
{13000} {1342F} {Egyptian Hieroglyphs}
{14400} {1467F} {Anatolian Hieroglyphs}
{16800} {16A3F} {Bamum Supplement}
{16A40} {16A6F} {Mro}
{16AD0} {16AFF} {Bassa Vah}
{16B00} {16B8F} {Pahawh Hmong}
{16F00} {16F9F} {Miao}
{16FE0} {16FFF} {Ideographic Symbols and Punctuation}
{17000} {187FF} {Tangut}
{18800} {18AFF} {Tangut Components}
{1B000} {1B0FF} {Kana Supplement}
{1BC00} {1BC9F} {Duployan}
{1BCA0} {1BCAF} {Shorthand Format Controls}
{1D000} {1D0FF} {Byzantine Musical Symbols}
{1D100} {1D1FF} {Musical Symbols}
{1D200} {1D24F} {Ancient Greek Musical Notation}
{1D300} {1D35F} {Tai Xuan Jing Symbols}
{1D360} {1D37F} {Counting Rod Numerals}
{1D400} {1D7FF} {Mathematical Alphanumeric Symbols}
{1D800} {1DAAF} {Sutton SignWriting}
{1E000} {1E02F} {Glagolitic Supplement}
{1E800} {1E8DF} {Mende Kikakui}
{1E900} {1E95F} {Adlam}
{1EE00} {1EEFF} {Arabic Mathematical Alphabetic Symbols}
{1F000} {1F02F} {Mahjong Tiles}
{1F030} {1F09F} {Domino Tiles}
{1F0A0} {1F0FF} {Playing Cards}
{1F100} {1F1FF} {Enclosed Alphanumeric Supplement}
{1F200} {1F2FF} {Enclosed Ideographic Supplement}
{1F300} {1F5FF} {Miscellaneous Symbols and Pictographs}
{1F600} {1F64F} {Emoticons}
{1F650} {1F67F} {Ornamental Dingbats}
{1F680} {1F6FF} {Transport and Map Symbols}
{1F700} {1F77F} {Alchemical Symbols}
{1F780} {1F7FF} {Geometric Shapes Extended}
{1F800} {1F8FF} {Supplemental Arrows-C}
{1F900} {1F9FF} {Supplemental Symbols and Pictographs}
{20000} {2A6DF} {CJK Unified Ideographs Extension B}
{2A700} {2B73F} {CJK Unified Ideographs Extension C}
{2B740} {2B81F} {CJK Unified Ideographs Extension D}
{2B820} {2CEAF} {CJK Unified Ideographs Extension E}
{2F800} {2FA1F} {CJK Compatibility Ideographs Supplement}
{E0000} {E007F} {Tags}
{E0100} {E01EF} {Variation Selectors Supplement}
{F0000} {FFFFF} {Supplementary Private Use Area-A}
{100000} {10FFFF} {Supplementary Private Use Area-BB}"

# Determine the unicode group of a specific printable character.
# Args:
#        c single unicode character to examine to examine.
# Returns:
#         index of first occurence, or -1if not found.
proc get_unicode_block { c } {

        # get hex value of the character
        set value [format %4.4X [scan $c %c]]
        foreach a [split $::unicode_blocks \n] {
                set from [lindex $a 0] 
                set to [lindex $a 1]
                if { $value >= $from && $value <= $to} { return [lindex $a 2] }

        return -1

# Retrieve position of first CJK character in string.
# Args:
#        str string to examine.
# Returns:
#         index of first occurence, or -1 if not found.
proc is_CJK { str } {
        set i 0
        foreach c [split $str ""] {
                if { [string first CJK [get_unicode_block $c] ] != -1 } { return $i }  
                incr i
        return -1


# test the code

# return first CJK Character, i.e. 善 
set str "{abhi-√bhū} {善能摧伏, 得勝, 得自在, 摧伏, 映奪}" 
puts [string index $str [is_CJK $str]]

# return location of first CJK character in string
puts [is_CJK "abhijña-jñāta 神通智"] ;# returns 14
puts [is_CJK "神通智"] ;# returns 0
puts [is_CJK Wolverhampton] ;# returns -1

KPV Two minor coding suggestions: First, if you make the variable unicode_blocks a list, then you can traipse over the list using foreach {from to who} $unicode_blocks { ... } This safer than relying on newlines in a long string which could easily get corrupted when copying the code around.

Second, it looks like you're relying on string comparisons of value against from and to. This may work if all the strings are the same size but it's much safer to convert the hex into a true number and compare values. Easiest fix is to prepend "0x" to every number entry in unicode_blocks and to get rid of the format command when setting the variable value.