function Utf8NextChar takes string utf8, integer index returns integer
     local integer hash = StringHash(SubString(utf8, index, index + 1))
     local boolean enhanced = false
     if hash >= 0x622796B0 then
         set enhanced = hash == 0x622796B0 or hash == 0x79680AB6
     elseif hash >= -0x2528FB81 then
         if hash >= 0x3CAF85D5 then
             if hash >= 0x56FE5F09 then
                 set enhanced = hash == 0x56FE5F09 or hash == 0x5B99BFC5
             else
                 set enhanced = hash == 0x3CAF85D5 or hash == 0x44F61401
             endif
         elseif hash >= -0x894A683 then
             set enhanced = hash == -0x894A683 or hash == 0x1A95F0E1
         else
             set enhanced = hash == -0x2528FB81 or hash == -0x15D74B40
         endif
     elseif hash >= -0x49701044 then
         if hash >= -0x41A7335B then
             set enhanced = hash == -0x41A7335B or hash == -0x3E754453
         else
             set enhanced = hash == -0x49701044 or hash == -0x473E9375
         endif
     elseif hash >= -0x5CCC4FE0 then
         set enhanced = hash == -0x5CCC4FE0 or hash == -0x4BEDA821
     else
         set enhanced = hash == -0x78635472 or hash == -0x65D3BCE0
     endif
     if enhanced then
         return index + 2
     endif
     return index + 1
endfunction

set length = StringLength(s)
set i = 0
loop
     set j = Utf8NextChar(s, i)
     exitwhen j > length
     set ch = SubString(s, i, j)
     //ch - очередной символ строки, производим с ним какие-либо действия.
     set i = j
endloop

function Utf8Length takes string utf8 returns integer
     local integer length = StringLength(utf8)
     local integer result = 0
     local integer i = 0
     local integer j
     loop
         set j = Utf8NextChar(utf8, i)
         exitwhen j > length
         set result = result + 1
         set i = j
     endloop
     return result
endfunction

//Преобразует число из диапазона [0 .. 15] в шестнадцатеричную форму.
function ToHexDigit takes integer digit returns string
     if digit < 8 then
         if digit < 4 then
             if digit < 2 then
                 if digit == 0 then
                     return "0"
                 endif
                 return "1"
             elseif digit == 2 then
                 return "2"
             endif
             return "3"
         elseif digit < 6 then
             if digit == 4 then
                 return "4"
             endif
             return "5"
         elseif digit == 6 then
             return "6"
         endif
         return "7"
     elseif digit < 0xC then
         if digit < 0xA then
             if digit == 8 then
                 return "8"
             endif
             return "9"
         elseif digit == 0xA then
             return "A"
         endif
         return "B"
     elseif digit < 0xE then
         if digit == 0xC then
             return "C"
         endif
         return "D"
     elseif digit == 0xE then
         return "E"
     endif
     return "F"
endfunction

//Преобразует строку с одной шестнадцатеричной цифрой в число.
function FromHexDigit takes string s returns integer
     if s == "0" then
         return 0
     elseif s == "1" then
         return 1
     elseif s == "2" then
         return 2
     elseif s == "3" then
         return 3
     elseif s == "4" then
         return 4
     elseif s == "5" then
         return 5
     elseif s == "6" then
         return 6
     elseif s == "7" then
         return 7
     elseif s == "8" then
         return 8
     elseif s == "9" then
         return 9
     elseif s == "A" then
         return 0xA
     elseif s == "B" then
         return 0xB
     elseif s == "C" then
         return 0xC
     elseif s == "D" then
         return 0xD
     elseif s == "E" then
         return 0xE
     endif
     return 0xF
endfunction

//Преобразует число из диапазона [0 .. 255] в шестнадцатеричную форму,
//добавляя при необходимости лидирующий нуль.
function ToColorHex takes integer x returns string
     local integer high = x / 16
     return ToHexDigit(high) + ToHexDigit(x - high * 16)
endfunction

//Преобразует двухсимвольную строку, содержащую шестнадцатеричную запись, в число.
function FromColorHex takes string hex returns integer
     return FromHexDigit(SubString(hex, 0, 1)) * 16 + FromHexDigit(SubString(hex, 1, 2))
endfunction

//Преобразует четверку чисел (alpha, red, green, blue) в цветовой код
//(включая управляющую последовательность "|c").
function GenerateColorCode takes integer a, integer r, integer g, integer b returns string
     return "|c" + ToColorHex(a) + ToColorHex(r) + ToColorHex(g) + ToColorHex(b)
endfunction

function GetGradientText takes string text, string leftColor, string rightColor returns string
     local integer transitions = Utf8Length(text) - 1
     local integer a = 0x00
     local integer r
     local integer g
     local integer b
     local integer da = 0
     local integer dr
     local integer dg
     local integer db
     local integer i = StringLength(leftColor)
     local integer j
     local boolean alphaExists = i == 8
     local string result = ""
     local string c

     if transitions < 0 then
         return ""
     endif

     //Предварительные преобразования, позволяющие распознавать цвета в любом формате,
     //включая произвольный регистр букв и отсутствие альфа-канала.
     set leftColor = StringCase(leftColor, true)
     if SubString(leftColor, 0, 2) == "|C" then
         set alphaExists = i == 10
     endif
     if alphaExists then
         set a = FromColorHex(SubString(leftColor, i - 8, i - 6))
         if transitions > 0 then
             set da = -a / transitions
         endif
     endif
     set r = FromColorHex(SubString(leftColor, i - 6, i - 4))
     set g = FromColorHex(SubString(leftColor, i - 4, i - 2))
     set b = FromColorHex(SubString(leftColor, i - 2, i))

     if transitions > 0 then
         set i = StringLength(rightColor)
         set alphaExists = i == 8
         set rightColor = StringCase(rightColor, true)
         if SubString(rightColor, 0, 2) == "|C" then
             set alphaExists = i == 10
         endif
         if alphaExists then
             set da = (FromColorHex(SubString(rightColor, i - 8, i - 6)) - a) / transitions
         endif
         set dr = (FromColorHex(SubString(rightColor, i - 6, i - 4)) - r) / transitions
         set dg = (FromColorHex(SubString(rightColor, i - 4, i - 2)) - g) / transitions
         set db = (FromColorHex(SubString(rightColor, i - 2, i)) - b) / transitions
     endif

     set i = 0
     loop
         set j = Utf8NextChar(text, i)
         set c = SubString(text, i, j)
         if c == " " then
             set result = result + " "
         else
             set result = result + GenerateColorCode(a, r, g, b) + c
         endif
         exitwhen transitions == 0
         set transitions = transitions - 1
         set a = a + da
         set r = r + dr
         set g = g + dg
         set b = b + db
         set i = j
     endloop
     return result + "|r"
endfunction