Skip to content
By using Twitter’s services you agree to our Cookies Use. We and our partners operate globally and use cookies, including for analytics, personalisation, and ads.

This is the legacy version of twitter.com. We will be shutting it down on June 1, 2020. Please switch to a supported browser, or disable the extension which masks your browser. You can see a list of supported browsers in our Help Center.

  • Home Home Home, current page.
  • About

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @
  • Language: English
    • Bahasa Indonesia
    • Bahasa Melayu
    • Català
    • Čeština
    • Dansk
    • Deutsch
    • English UK
    • Español
    • Filipino
    • Français
    • Hrvatski
    • Italiano
    • Magyar
    • Nederlands
    • Norsk
    • Polski
    • Português
    • Română
    • Slovenčina
    • Suomi
    • Svenska
    • Tiếng Việt
    • Türkçe
    • Ελληνικά
    • Български език
    • Русский
    • Српски
    • Українська мова
    • עִבְרִית
    • العربية
    • فارسی
    • मराठी
    • हिन्दी
    • বাংলা
    • ગુજરાતી
    • தமிழ்
    • ಕನ್ನಡ
    • ภาษาไทย
    • 한국어
    • 日本語
    • 简体中文
    • 繁體中文
  • Have an account? Log in
    Have an account?
    · Forgot password?

    New to Twitter?
    Sign up
pcwalton's profile
Patrick Walton
Patrick Walton
Patrick Walton
@pcwalton

Tweets

Patrick Walton

@pcwalton

Research engineer at Mozilla

San Francisco, CA
pcwalton.github.io
Joined November 2009

Tweets

  • © 2020 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Imprint
  • Cookies
  • Ads info
Dismiss
Previous
Next

Go to a person's profile

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @

Promote this Tweet

Block

  • Tweet with a location

    You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more

    Your lists

    Create a new list


    Under 100 characters, optional

    Privacy

    Copy link to Tweet

    Embed this Tweet

    Embed this Video

    Add this Tweet to your website by copying the code below. Learn more

    Add this video to your website by copying the code below. Learn more

    Hmm, there was a problem reaching the server.

    By embedding Twitter content in your website or app, you are agreeing to the Twitter Developer Agreement and Developer Policy.

    Preview

    Why you're seeing this ad

    Log in to Twitter

    · Forgot password?
    Don't have an account? Sign up »

    Sign up for Twitter

    Not on Twitter? Sign up, tune into the things you care about, and get updates as they happen.

    Sign up
    Have an account? Log in »

    Two-way (sending and receiving) short codes:

    Country Code For customers of
    United States 40404 (any)
    Canada 21212 (any)
    United Kingdom 86444 Vodafone, Orange, 3, O2
    Brazil 40404 Nextel, TIM
    Haiti 40404 Digicel, Voila
    Ireland 51210 Vodafone, O2
    India 53000 Bharti Airtel, Videocon, Reliance
    Indonesia 89887 AXIS, 3, Telkomsel, Indosat, XL Axiata
    Italy 4880804 Wind
    3424486444 Vodafone
    » See SMS short codes for other countries

    Confirmation

     

    Welcome home!

    This timeline is where you’ll spend most of your time, getting instant updates about what matters to you.

    Tweets not working for you?

    Hover over the profile pic and click the Following button to unfollow any account.

    Say a lot with a little

    When you see a Tweet you love, tap the heart — it lets the person who wrote it know you shared the love.

    Spread the word

    The fastest way to share someone else’s Tweet with your followers is with a Retweet. Tap the icon to send it instantly.

    Join the conversation

    Add your thoughts about any Tweet with a Reply. Find a topic you’re passionate about, and jump right in.

    Learn the latest

    Get instant insight into what people are talking about now.

    Get more of what you love

    Follow more accounts to get instant updates about topics you care about.

    Find what's happening

    See the latest conversations about any topic instantly.

    Never miss a Moment

    Catch up instantly on the best stories happening as they unfold.

    1. Henri Sivonen‏ @hsivonen 8 Sep 2019
      • Report Tweet
      • Report NetzDG Violation

      I wrote about string length: https://hsivonen.fi/string-length/ 

      16 replies 206 retweets 512 likes
    2. gankra's gay‏ @Gankra_ 8 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @hsivonen

      As of swift 5.0, String is largely ABI-stabilized and inlineable. Storage length is stored, but not the EGC count, which is O(n). "the" length being slow isn't a ~big deal give the stdlib's design. (yay iterators!) also interesting: they store/maintain "isASCII" and "isNFC"pic.twitter.com/aTVpRz5Nj0

      screenshot of some code comments: https://github.com/apple/swift/blob/master/stdlib/public/core/StringObject.swift#L576-L615
      1 reply 0 retweets 15 likes
    3. gankra's gay‏ @Gankra_ 8 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Gankra_ @hsivonen

      isNFC is interesting because swift *also* defines the default string comparison operations to use the NFC version of the string contents, which is a much more bold/interesting decision than the length issue (Rust using raw utf8 byte comparison is very semantically dubious)

      2 replies 1 retweet 10 likes
    4. Patrick Walton‏ @pcwalton 8 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Gankra_ @hsivonen

      Is it though? Swift’s decision means that any hash function has to be very careful to hash the NFC version of the string. Otherwise hash and == will differ, corrupting hash tables. Rust’s decision seems more resistant to misuse.

      1 reply 0 retweets 3 likes
    5. gankra's gay‏ @Gankra_ 8 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @pcwalton @hsivonen

      I don't understand what misuse you're possibly picturing -- keep in mind Rust's Vec<u8> and String do not hash the same.

      1 reply 0 retweets 0 likes
      Patrick Walton‏ @pcwalton 8 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Gankra_ @hsivonen

      A custom hash table that implements hash by hashing the bytes of the string using some application-specific hash function and uses == for equality.

      9:49 AM - 8 Sep 2019
      • 1 Like
      • Farseen Abdul Salam
      1 reply 0 retweets 1 like
        1. New conversation
        2. Patrick Walton‏ @pcwalton 8 Sep 2019
          • Report Tweet
          • Report NetzDG Violation
          Replying to @pcwalton @Gankra_ @hsivonen

          Also, does NFC change from Unicode version to Unicode version? If so, this could cause incompatibility issues in Swift code similar to the ones that Henri described with EGC.

          3 replies 0 retweets 4 likes
        3. Henri Sivonen‏ @hsivonen 8 Sep 2019
          • Report Tweet
          • Report NetzDG Violation
          Replying to @pcwalton @Gankra_

          Normalization can change for currently-unassigned code points, yes. That's why IDNA standardizes on an arbitrary version of Unicode.

          0 replies 0 retweets 3 likes
        4. End of conversation

      Loading seems to be taking a while.

      Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.

        Promoted Tweet

        false

        • © 2020 Twitter
        • About
        • Help Center
        • Terms
        • Privacy policy
        • Imprint
        • Cookies
        • Ads info