
Attach (recommended) or Link to PDF file here:
[NAPEN16171380959.pdf](https://github.com/mozilla/pdf.js/files/6143802/NAPEN16171380959.pdf)

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- Operating system and its version: Windows 10
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}
      
      return (charsCache[charsCacheKey] = glyphs);
    },
    /**
     * Chars can have different sizes (depends on the encoding).
     * @param {String} a string encoded with font encoding.
     * @returns {Array<Array<number>>} the positions of each char in the string.
     */
    getCharPositions(chars) {
      
      
      const positions = [];
      if (this.cMap) {
        const c = Object.create(null);
        let i = 0;
        while (i < chars.length) {
          this.cMap.readCharCode(chars, i, c);
          const length = c.length;
          positions.push([i, i + length]);
          i += length;
        }
      } else {
        for (let i = 0, ii = chars.length; i < ii; ++i) {
          positions.push([i, i + 1]);
        }
      }
      return positions;
    },
    get glyphCacheValues() {