# \`Base.Printf.ini\_dec\` has a fall-thru issue

**URL:** <https://discourse.julialang.org/t/base-printf-ini-dec-has-a-fall-thru-issue/27247>\
**Category:** Internals & Design\
**Created:** [August 6, 2019, 11:48pm UTC](https://discourse.julialang.org/t/base-printf-ini-dec-has-a-fall-thru-issue/27247 "2019-08-06T23:48:55Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![JeffreySarnoff](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jeffreysarnoff/32/1980_2.png) [@JeffreySarnoff](https://discourse.julialang.org/u/JeffreySarnoff)\
**Post date:** [August 6, 2019, 11:48pm UTC](https://discourse.julialang.org/t/base-printf-ini-dec-has-a-fall-thru-issue/27247/1 "2019-08-06T23:48:55Z")

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Some of my more precise floating point types do not properly know how to overload `Base.Printf.ini_dec` or any of its very close algorithmic partners `Printf.fix_dec` `Printf.decode_dec` (nor which of those should be given special handling). I understand that the `abc_dec` functions are intended to include fall-back implementations that handle or otherwise appropriately pass through a value-consistent result.

Here is some code that fails at the moment: [https://github.com/JuliaMath/DoubleFloats.jl/issues/81](https://github.com/JuliaMath/DoubleFloats.jl/issues/81)

Something is not fully sewn on that side. I would like to know what I should provide within `DoubleFloats` that would allow the values to proceed through the Printf setup and construction correctly. And also what special Base-internal (not exported functionality would be helpful).

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**Author:** ![quinnj](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/quinnj/32/11_2.png) [@quinnj](https://discourse.julialang.org/u/quinnj)\
**Post date:** [August 7, 2019, 1:04pm UTC](https://discourse.julialang.org/t/base-printf-ini-dec-has-a-fall-thru-issue/27247/2 "2019-08-07T13:04:10Z")

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Posted my thoughts [here](https://github.com/JuliaMath/DoubleFloats.jl/issues/81#issuecomment-519086920)