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JavaScript

var stringToParse = "{vertices:[-1.0, -1.0, -1.0, -1.0, -1.0, 0.0, 1.0, -1.0, 0.0]}";

Object.prototype.simpleParse = function() {
    if (!(this instanceof String)) throw "Type mismatch";
    var re = /(\w+)[^:]+:\[([^\]]+)\]/g;
    var keyvalues = re.exec(this.valueOf());
    var key = keyvalues[1];
    var values = keyvalues[2].split(",");
    var arr = [];
    for (val in values) {
        var currentValue = (/-?\d+(.\d+)?/).exec(values[val])[0];
        arr.push(currentValue);
    }
    arr.pop();
    ret = {};
    ret[key] = new Float32Array(arr);
    return ret;
}

console.log(stringToParse.simpleParse());