# \#hack

**URL:** https://discourse.julialang.org/tag/hack/728.md

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## [Change a struct in place](https://discourse.julialang.org/t/change-a-struct-in-place/63914)

<div class="topic-metadata">

**Author:** [@jzr](https://discourse.julialang.org/u/jzr)\
**Replies:** 20\
**Last updated:** [July 2, 2021, 11:16am UTC](https://discourse.julialang.org/t/change-a-struct-in-place/63914 "2021-07-02T11:16:36Z")

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I made a struct with Float32 julia\> struct Foo x::Float32 end julia\> foo = Foo(1) Foo(1.0f0) But now I realized Float32 isn’t big enough and I want Float64, and I want the change to propagate to the ins…