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indragiek/generics.swift

Last active August 29, 2015 14:13
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This code doesn't compile (Xcode 6.1.1, Swift 1.1)
Raw
generics.swift
public protocol TableViewSectionType {
typealias ItemCollection: CollectionType
}
public protocol TableViewCellFactoryType {
typealias Item
}
public final class TableViewDataSource<
SectionCollection: CollectionType,
Factory: TableViewCellFactoryType
where
SectionCollection.Generator.Element: TableViewSectionType,
SectionCollection.Generator.Element.ItemCollection.Generator.Element == Factory.Item // Changing this to a concrete type like Int fixes it
> {
}
@indragiek
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This code doesn't compile under Swift 1.1:

Command failed due to signal: Segmentation fault: 11
...
1.  While emitting IR for source file /Users/Karunaratne/Desktop/sandbox/sandbox/generics.swift
2.  While emitting class metadata for 'TableViewDataSource' at /Users/Karunaratne/Desktop/sandbox/sandbox/generics.swift:19:14

If I change this constraint:

SectionCollection.Generator.Element.ItemCollection.Generator.Element == Factory.Item

to use a concrete type like Int rather than Factory.Item, the code compiles successfully.

Compiler bug or am I doing something wrong?

@indragiek
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Swapping the order of SectionCollection and Factory in the generic type parameter list seems to have fixed it. Probably a bug, then.

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