# How do I set bounds for a parametric subtype of a parametric abstract type?

**URL:** <https://discourse.julialang.org/t/how-do-i-set-bounds-for-a-parametric-subtype-of-a-parametric-abstract-type/122101>\
**Category:** New to Julia\
**Tags:** type, parametric-types\
**Created:** [October 31, 2024, 11:46pm UTC](https://discourse.julialang.org/t/how-do-i-set-bounds-for-a-parametric-subtype-of-a-parametric-abstract-type/122101 "2024-10-31T23:46:04Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![kapple](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/kapple/32/218915_2.png) [@kapple](https://discourse.julialang.org/u/kapple)\
**Post date:** [November 1, 2024, 1:42am UTC](https://discourse.julialang.org/t/how-do-i-set-bounds-for-a-parametric-subtype-of-a-parametric-abstract-type/122101/2 "2024-11-01T01:42:32Z")

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Yeah this part of Julia syntax is sometimes tricky for me in remembering how to specify the parametric type’s bounds.

I also see your choice of a name for your subtype suggests your level of frustration 😅 in fact [you’re not alone in this frustration](https://discourse.julialang.org/t/why-isnt-this-legal-syntax-for-defining-a-subtype/121479).

As in thread I linked, the working syntax is

```julia
abstract type Dummy{T} end

struct EstoTieneSentido{T <: Real} <: Dummy{T}
    a::Float64
    b::T
end

```

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