How to use the benchmark.map function in benchmark

startLine: function(name) {
    var winners = Benchmark.map(this.winners(this.currentBenches), function(bench) {
      return bench.name.split(": ")[1];
    });

    this.currentBenches = [];

    print(winners.join(", "));
    print("\n");
    var padding = this.nameSize - name.length + 1;
    name = name + new Array(padding).join(" ");
    print(name);
  },
  writeBench: function(bench) {

startLine: function(name) {
    var winners = Benchmark.map(this.winners(this.currentBenches), function(bench) {
      return bench.name.split(": ")[1];
    });

    this.currentBenches = [];

    print(winners.join(", "));
    print("\n");

    if (name) {
      this.writeValue(name);
    }
  },
  writeBench: function(bench) {

startLine: function(name) {
    var winners = Benchmark.map(this.winners(this.currentBenches), function(
      bench
    ) {
      return bench.name.split(': ')[1];
    });

    this.currentBenches = [];

    print(winners.join(', '));
    print('\n');

    if (name) {
      this.writeValue(name);
    }
  },
  writeBench: function(bench) {