# Why can't we merge Missing and Nothing?

**URL:** <https://discourse.julialang.org/t/why-cant-we-merge-missing-and-nothing/25793>\
**Category:** Internals & Design\
**Created:** [June 28, 2019, 10:03am UTC](https://discourse.julialang.org/t/why-cant-we-merge-missing-and-nothing/25793 "2019-06-28T10:03:59Z")\
**Posts on this page:** 1\
**Showing post:** 9

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**Author:** ![HFriberg-mosek](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/hfriberg-mosek/32/8376_2.png) [@HFriberg-mosek](https://discourse.julialang.org/u/HFriberg-mosek)\
**Post date:** [July 3, 2019, 5:46pm UTC](https://discourse.julialang.org/t/why-cant-we-merge-missing-and-nothing/25793/9 "2019-07-03T17:46:29Z")

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Say I develop a package to generate data from some source (e.g., scanning webpages). When a data point cannot be fetched, should I mark it using `Missing` or `Nothing`? It seems the generator of data, not the user of this data, decides which operations are allowed on it?

My take on it would be that the user should either generate the data with a specific behavior in mind (parsing the desired type), or generate it using `Nothing` (the default) and then convert to `Missing` where appropriate. Can this conversion be done fast? Is this the most appropriate solution?

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