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Exponential type checking time of nested Tuples
See original GitHub issueThis example complies in ~16 seconds on my machine, and goes to ~32 seconds with one additional level of nesting.
object Example {
case class C[H, T](h: H, t: T)
type I = Int
val p
: C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,C[I,I]]]]]]]]]]]]]]]]]]]]]]]
= C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,C(1,1)))))))))))))))))))))))
}
This explosion only happens when both the type and the value are provided, commenting the : line or replacing the = line with = ??? leads to normal compilation times. For some reason things work fine when replacing C with Tuple2.
Issue Analytics
- State:
- Created 7 years ago
- Comments:7 (7 by maintainers)
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This example now compiles in 3 seconds for me, and the compilation time does not seem to significantly increase when adding more nesting. Closing.
See also https://bugs.openjdk.java.net/browse/JDK-8055984 / https://bugs.openjdk.java.net/browse/JDK-8046685 / http://hg.openjdk.java.net/jdk9/dev/langtools/rev/3793a6706e58 for some similar problems+solutions form javac.