https://issues.dlang.org/show_bug.cgi?id=8947

tetyys@tetyys.com changed:

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--- Comment #1 from tetyys@tetyys.com ---
It's because you're calling https://github.com/dlang/phobos/blob/master/std/container/rbtree.d#L1836 which resolves you to having tree of integers, thus "t2.stableInsert(1)" is not wrong.

To have a tree of array of integers, do "redBlackTree([ a ])".

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