# Problems with deprecations of islower, lowercase, isupper, uppercase

**URL:** <https://discourse.julialang.org/t/problems-with-deprecations-of-islower-lowercase-isupper-uppercase/7797>\
**Category:** Internals & Design\
**Created:** [December 15, 2017, 8:19pm UTC](https://discourse.julialang.org/t/problems-with-deprecations-of-islower-lowercase-isupper-uppercase/7797 "2017-12-15T20:19:32Z")\
**Posts on this page:** 1\
**Showing post:** 100

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**Author:** ![Liso](https://avatars.discourse-cdn.com/v4/letter/l/898d66/32.png) [@Liso](https://discourse.julialang.org/u/Liso)\
**Post date:** [December 21, 2017, 2:35pm UTC](https://discourse.julialang.org/t/problems-with-deprecations-of-islower-lowercase-isupper-uppercase/7797/100 "2017-12-21T14:35:04Z")

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Is `Str{T} <: AbstractString` necessary?

And probably you could show performance gain from using `Str{T}` [here](https://discourse.julialang.org/t/wip-faster-string-sort/7671/33)?

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