Function getLeftFormatIndex

docs/app/js/sanddance-app.js:50892–50897

(maskCharData, index)

    return maskCharData[maskCharData.length - 1].displayIndex;
}
function getLeftFormatIndex(maskCharData, index) {
    for(var i = maskCharData.length - 1; i >= 0; i--){
        if (maskCharData[i].displayIndex < index) return maskCharData[i].displayIndex;
    }
    return maskCharData[0].displayIndex;
}
function clearRange(maskCharData, selectionStart, selectionCount) {
    for(var i = 0; i < maskCharData.length; i++)if (maskCharData[i].displayIndex >= selectionStart) {
        if (maskCharData[i].displayIndex >= selectionStart + selectionCount) break;