# Could any of you point me to the description of the double dot record wild card syntax?

**URL:** <https://forum.canton.network/t/could-any-of-you-point-me-to-the-description-of-the-double-dot-record-wild-card-syntax/2111>\
**Category:** App Development\
**Created:** [February 17, 2021, 7:32pm UTC](https://forum.canton.network/t/could-any-of-you-point-me-to-the-description-of-the-double-dot-record-wild-card-syntax/2111 "2021-02-17T19:32:42Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![gyorgybalazsi](https://yyz2.discourse-cdn.com/flex034/user_avatar/forum.canton.network/gyorgybalazsi/32/684_2.png) [@gyorgybalazsi](https://forum.canton.network/u/gyorgybalazsi)\
**Post date:** [February 17, 2021, 7:32pm UTC](https://forum.canton.network/t/could-any-of-you-point-me-to-the-description-of-the-double-dot-record-wild-card-syntax/2111/1 "2021-02-17T19:32:42Z")

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Like this one:

 ![image](https://canada1.discourse-cdn.com/flex028/uploads/daml/original/2X/1/1c8805b65b74b05ab0128884f91636955498aee3.png)

I cannot remember how I learnt it.

The Haskell version: [6.5.7. Record wildcards — Glasgow Haskell Compiler 9.1.20210216 User's Guide](https://ghc.gitlab.haskell.org/ghc/doc/users_guide/exts/record_wildcards.html)

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**Author:** ![gyorgybalazsi](https://yyz2.discourse-cdn.com/flex034/user_avatar/forum.canton.network/gyorgybalazsi/32/684_2.png) [@gyorgybalazsi](https://forum.canton.network/u/gyorgybalazsi)\
**Post date:** [February 17, 2021, 7:58pm UTC](https://forum.canton.network/t/could-any-of-you-point-me-to-the-description-of-the-double-dot-record-wild-card-syntax/2111/2 "2021-02-17T19:58:53Z")

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In the tutorial it’s called “record punning” syntax:

We use Daml’s `..` record punning syntax to avoid boilerplate code in the pure upgrade functions like `upgradeUser. User{..}` brings all the fields of the User template in scope and

> **[Learn Damlsmart contract Language - Interactive Learning Tutorials](https://daml.com/learn/upgrading/upgrade-running-applications)**
>
> Our interactive tutorials provide you with a pre-configured instance, accessible from your browser without any downloads or configuration.

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**Author:** ![cocreature](https://yyz2.discourse-cdn.com/flex034/user_avatar/forum.canton.network/cocreature/32/36_2.png) [@cocreature](https://forum.canton.network/u/cocreature)\
**Post date:** [February 17, 2021, 8:08pm UTC](https://forum.canton.network/t/could-any-of-you-point-me-to-the-description-of-the-double-dot-record-wild-card-syntax/2111/3 "2021-02-17T20:08:10Z")

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What exactly are you looking for? You’ve already linked to the description of `RecordWildCards` which is what the feature is called in Haskell. We just inherit it from there so it should work exactly the same.

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**Author:** ![gyorgybalazsi](https://yyz2.discourse-cdn.com/flex034/user_avatar/forum.canton.network/gyorgybalazsi/32/684_2.png) [@gyorgybalazsi](https://forum.canton.network/u/gyorgybalazsi)\
**Post date:** [February 17, 2021, 9:22pm UTC](https://forum.canton.network/t/could-any-of-you-point-me-to-the-description-of-the-double-dot-record-wild-card-syntax/2111/4 "2021-02-17T21:22:59Z")

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Yes, thank you, thought I can find it in the Daml docs somewhere