`MethodError` thrown while preparing to throw `InexactError` in conversion of `Rational` to `Integer` or `Complex` to `Real`

Minimal reproducer:

```julia-repl
julia> struct A <: Integer end

julia> struct B <: Integer end

julia> Union{A,B}(1//2)
ERROR: MethodError: no method matching nameof(::Type{Union{A, B}})
The function `nameof` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  nameof(::Core.IntrinsicFunction)
   @ Base reflection.jl:2369
  nameof(::Module)
   @ Base essentials.jl:401
  nameof(::UnionAll)
   @ Base reflection.jl:343
  ...

Stacktrace:
 [1] Union{A, B}(x::Rational{Int64})
   @ Base ./rational.jl:151
 [2] top-level scope
   @ REPL[3]:1
```

It's not valid to call `nameof` on an arbitrary subtype of `Integer`, because it may be an `Union`:

https://github.com/JuliaLang/julia/blob/945517ba4e15f7470b8790a696ba5404ef047f2f/base/rational.jl#L149-L152

It seems like this could be fixed by simply replacing the `nameof` call with `:convert`.

	Bool(x::Rational) = x==0 ? false : x==1 ? true :
	throw(InexactError(:Bool, Bool, x)) # to resolve ambiguity
	(::Type{T})(x::Rational) where {T<:Integer} = (isinteger(x) ? convert(T, x.num)::T :
	throw(InexactError(nameof(T), T, x)))

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`MethodError` thrown while preparing to throw `InexactError` in conversion of `Rational` to `Integer` or `Complex` to `Real` #55756

nsajko
openedon Sep 12, 2024

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MethodError thrown while preparing to throw InexactError in conversion of Rational to Integer or Complex to Real #55756

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nsajkoopenedon Sep 12, 2024

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