ZScript_UTF8Str.cs

/*
 * This is free and unencumbered software released into the public domain.
 *
 * Anyone is free to copy, modify, publish, use, compile, sell, or distribute
 * this software, either in source code form or as a compiled binary, for any
 * purpose, commercial or non-commercial, and by any means.
 *
 * In jurisdictions that recognize copyright laws, the author or authors of this
 * software dedicate any and all copyright interest in the software to the public
 * domain. We make this dedication for the benefit of the public at large and to
 * the detriment of our heirs and successors. We intend this dedication to be an
 * overt act of relinquishment in perpetuity of all present and future rights to
 * this software under copyright law.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * For more information, please refer to http://unlicense.org/
*/
// Credits in the form of my name (Chronos "phantombeta" Ouroboros) and a link to this page would be appreciated, however.

    static string Left (string str, int numChars) {
        int strLen = str.CodePointCount ();
        if (strLen < numChars)
            numChars = strLen;

        int curPos = 0;
        for (int i = 0; i < numChars; i++) {
            int c;
            [c, curPos] = str.GetNextCodePoint (curPos);
        }

        return str.Left (curPos);
    }

    static string Mid (string str, int startChar, int numChars) {
        int strLen = str.CodePointCount ();

        if (startChar >= strLen)
            return "";

        if (startChar + numChars > strLen || startChar + numChars < startChar)
            numChars = strLen - startChar;
        int charCount = startChar + numChars;

        int startPos;
        int prevPos;
        int curPos = 0;
        for (int i = 0; i < charCount; i++) {
            if (i == startChar)
                startPos = curPos;

            prevPos = curPos;
            int c;
            [c, curPos] = str.GetNextCodePoint (curPos);

            if (i == charCount - 1)
                break;
        }

        return str.Mid (startPos, curPos - startPos);
    }