Function charWidth

docs/welcome/lib/executr/lib/CodeMirror/codemirror.js:1128–1136

(display)

  }

  function charWidth(display) {
    if (display.cachedCharWidth != null) return display.cachedCharWidth;
    var anchor = elt("span", "x");
    var pre = elt("pre", [anchor]);
    removeChildrenAndAdd(display.measure, pre);
    var width = anchor.offsetWidth;
    if (width > 2) display.cachedCharWidth = width;
    return width || 10;
  }

  // OPERATIONS