# Why is the meaning of \`:\` and \`::\` swapped in Daml vs. Haskell

**URL:** <https://forum.canton.network/t/why-is-the-meaning-of-and-swapped-in-daml-vs-haskell/5408>\
**Category:** App Development\
**Created:** [October 12, 2022, 2:03am UTC](https://forum.canton.network/t/why-is-the-meaning-of-and-swapped-in-daml-vs-haskell/5408 "2022-10-12T02:03:07Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![mesch](https://yyz2.discourse-cdn.com/flex034/user_avatar/forum.canton.network/mesch/32/3248_2.png) [@mesch](https://forum.canton.network/u/mesch)\
**Post date:** [October 12, 2022, 2:03am UTC](https://forum.canton.network/t/why-is-the-meaning-of-and-swapped-in-daml-vs-haskell/5408/1 "2022-10-12T02:03:07Z")

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We repeatedly got confused by `:` used for type declarations and `::` for the `cons` operator in Daml, which is just swapped from Haskell.

So just curious, why that choice? Is there a backstory?

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**Author:** ![Matteo\_Limberto](https://yyz2.discourse-cdn.com/flex034/user_avatar/forum.canton.network/matteo_limberto/32/2823_2.png) [@Matteo\_Limberto](https://forum.canton.network/u/Matteo_Limberto)\
**Post date:** [October 12, 2022, 6:38am UTC](https://forum.canton.network/t/why-is-the-meaning-of-and-swapped-in-daml-vs-haskell/5408/2 "2022-10-12T06:38:52Z")

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Hi @mesch,

I believe [this post](https://medium.com/daml-driven/four-tweaks-to-improve-haskell-b1de9c87f816) on Medium delves into the subject.

Thanks,  
Matteo