var res = 0; var nums = [1,2,3,4,5,6,7,8,9]; $.each(nums, function(i, v) { res = v; if (res === 5) { return false; } return true; }); console.assert(res === 5); _.each(nums, function(v, i) { res = v; if (res === 5) { return false; } return true; }); console.assert(res === 9); // _.someでbreak _.some(nums, function(v, i) { res = v; if (res === 5) { return true; } return false; }); console.assert(res