Benchmark: for-in vs object.keys (4)

Script Preparation code:

var obj = {
  quitMin: 'mod+q',
  addTab: 'mod+t',
  addPrivateTab: 'shift+mod+n',
  duplicateTab: 'shift+mod+d',
  addTask: 'mod+n',
  toggleTasks: 'shift+mod+e',
  goBack: 'mod+left',
  goForward: 'mod+right',
  enterEditMode: ['mod+l', 'mod+k'],
  runShortcut: 'mod+e',
  completeSearchbar: 'mod+enter',
  closeTab: 'mod+w',
  restoreTab: 'shift+mod+t',
  gotoFirstTab: 'shift+mod+9',
  gotoLastTab: 'mod+9',
  addToFavorites: 'mod+d',
  showBookmarks: 'shift+mod+b',
  toggleReaderView: 'shift+mod+r',
  switchToNextTab: ['option+mod+right', 'ctrl+tab', 'shift+mod+pagedown'],
  switchToPreviousTab: ['option+mod+left', 'shift+ctrl+tab', 'shift+mod+pageup'],
  moveTabLeft: 'option+mod+shift+left',
  moveTabRight: 'option+mod+shift+right',
  switchToNextTask: 'mod+]',
  switchToPreviousTask: 'mod+[',
  closeAllTabs: 'shift+mod+w',
  reload: ['mod+r', 'f5'],
  reloadIgnoringCache: 'mod+f5',
  showMenu: 'ctrl+m',
  followLink: 'mod+enter',
  fillPassword: 'mod+\\',
  toggleTabAudio: 'shift+mod+m',
  showHistory: 'shift+mod+h'
};

Tests:

for-in
for (var i=100; i > 0; i--) { for (const key in obj) { console.log(key); } }
Object.keys
for (var i=100; i > 0; i--) { for(const key of Object.keys(obj)) { console.log(key) } }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for-in
Object.keys

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks!

**Benchmark Definition**

The provided JSON represents a benchmark definition, which outlines the test to be performed on JavaScript engines. In this case, we have two individual test cases:

1. `for-in`
2. `Object.keys`

**What is being tested?**

Both test cases are designed to measure the performance of iterating over an object's keys using different methods.

The first test case uses a traditional `for` loop with an `in` keyword: `for (var i=100; i > 0; i--) { for (const key in obj) { console.log(key); } }`

The second test case uses the `Object.keys()` method to iterate over the object's keys: `for (var i=100; i > 0; i--) { for(const key of Object.keys(obj)) { console.log(key) } }`

**Options compared**

We have two options being compared:

A. Traditional `for-in` loop
B. Using `Object.keys()` method

**Pros and Cons of each approach:**

1. **Traditional `for-in` loop:**
	* Pros:
		+ Wide support across older JavaScript engines.
		+ May be faster for small objects, as it avoids the overhead of `Object.keys()`.
	* Cons:
		+ Can lead to slower performance for large objects due to the use of an array-like object and its iterator.
		+ Requires more manual handling of iteration boundaries (e.g., skipping iteration when `i` reaches 0).
2. **Using `Object.keys()` method:**
	* Pros:
		+ More modern and widely supported, suitable for most modern JavaScript engines.
		+ Provides a concise way to iterate over an object's keys without manual array-like object management.
	* Cons:
		+ May be slower than the traditional `for-in` loop due to additional overhead from creating an iterator.

**Other considerations:**

1. **Library usage:** Neither test case uses any external libraries, so we're focusing solely on JavaScript engine performance optimizations.
2. **Special JS features:** There are no special JS features or syntax used in these benchmark definitions. They're straightforward examples of iterating over object keys using different methods.

**Alternatives:**

If you wanted to explore alternative approaches, you could consider:

1. Using a custom iterator (e.g., `Array.prototype[Symbol.iterator]`) instead of `Object.keys()`.
2. Implementing a custom iteration loop without using `for-in` or `Object.keys()` (e.g., using `while` loops and manual array-like object management).
3. Comparing performance with different optimization techniques, such as caching iterator results or optimizing boundary conditions.

Keep in mind that each alternative would require significant changes to the benchmark definition and test cases.

Related benchmarks:

for-in vs object.keys (4) (version: 0)

Comparing performance of: for-in vs Object.keys

Created: 4 years ago by: Guest

Jump to the latest result

for-in

Object.keys

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):