Swift looses generic type information when casting [Any] to more specific type with as? operator
| Originator: | ilyapuchka | ||
| Number: | rdar://23532339 | Date Originated: | 13.10.15 |
| Status: | Open | Resolved: | |
| Product: | Swift | Product Version: | 2.1 |
| Classification: | Developer Tools | Reproducible: |
If I have instances of some generic type stored in array of Any and try to upcast this array to more specific type using as? operator and iterate it, it will cause crash at runtime on access to array item, but only on _second_ iteration of loop. If instead I iterate array as array of Any and upcast each individual item inside loop body it works as expected. Bug is demonstrated in this gist https://gist.github.com/ilyapuchka/28aee3ac5af4133ec93d and in attached playground
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