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Update const_eval.md for feature stabilization #1166

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8 changes: 3 additions & 5 deletions src/const_eval.md
Original file line number Diff line number Diff line change
Expand Up @@ -65,8 +65,8 @@ A _const context_ is one of the following:

A _const fn_ is a function that one is permitted to call from a const context. Declaring a function
`const` has no effect on any existing uses, it only restricts the types that arguments and the
return type may use, as well as prevent various expressions from being used within it. You can freely do anything with a const function that
you can do with a regular function.
return type may use, as well as prevent various expressions from being used within it. You can freely
do anything with a const function that you can do with a regular function.

When called from a const context, the function is interpreted by the
compiler at compile time. The interpretation happens in the
Expand All @@ -84,13 +84,11 @@ slightly) different results. It is advisable to not make array lengths and enum
discriminants depend on floating point computations.


Notable features that const contexts have, but const fn haven't are:
Notable features that are allowed in const contexts but not in const functions include:

* floating point operations
* floating point values are treated just like generic parameters without trait bounds beyond
`Copy`. So you cannot do anything with them but copy/move them around.
* `dyn Trait` types
* generic bounds on generic parameters beyond `Sized`
* comparing raw pointers
* union field access
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