Fix conversion Irrational => Rational #16527
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simonbyrne
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| @@ -13,7 +13,22 @@ promote_rule{s,T<:Number}(::Type{Irrational{s}}, ::Type{T}) = promote_type(Float | |||
| convert(::Type{AbstractFloat}, x::Irrational) = Float64(x) | |||
| convert(::Type{Float16}, x::Irrational) = Float16(Float32(x)) | |||
| convert{T<:Real}(::Type{Complex{T}}, x::Irrational) = convert(Complex{T}, convert(T,x)) | |||
| convert{T<:Integer}(::Type{Rational{T}}, x::Irrational) = convert(Rational{T}, Float64(x)) | |||
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| @generated function convert{T<:Integer}(::Type{Rational{T}}, x::Irrational) | |||
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Maybe I am mistaken but this doesn't seem to return an expression like a nvm@generated function should. It also doesn't really seem to need to be a @generated function at all.
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Returning a value is okay (it just gets spliced in as an expression).
The aim of the @generated is to get it to perform the calculation at compile time, as the result will always be constant. This is exactly the same as the usage in the function directly below.
Technically, an @pure annotation would be sufficient , once #14324 is sorted out.
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I think putting @pure on this function would just work.
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I tried, it didn't.
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| p = 256 | ||
| while true | ||
| setprecision(BigFloat, p) | ||
| bx = BigFloat(x()) |
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how does this work? I get
julia> pi()
ERROR: MethodError: objects of type Irrational{:π} are not callable
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It seems that x == typeof(pi):
julia> @generated function foo(x) x end
foo (generic function with 1 method)
julia> foo(pi)
Irrational{:π}
julia> foo(pi)()
π = 3.1415926535897...
Is that a bug?
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right, no, this is a generated function, this is how they're supposed to work which I just keep forgetting
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Going to crosspost this from #16513. Is this operation meaningful? Non-exact operations on Also, converting from an |
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@TotalVerb This pr does not depart from anything. This only fixes a roundoff error (on a dubious conversion). It would be a different issue to just remove the conversion (with a @simonbyrne Given the confusions about (Maybe something like) # This is a @generated function because it allows the actual calculation to be performed compile-time
# Note that it returns a Rational constant that get's spliced into the AST of the caller |
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At the moment, the
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Fixes #16513. Changes generated macro to pure macro, so as to avoid breaking in future compiler changes.
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Using Should be ready to merge. |
Fixes JuliaLang#16513. Changes generated macro to pure macro, so as to avoid breaking in future compiler changes.
Fixes #16513.