Ah, sorry, missed the lack of parentheses... This works as expected:
Pike v7.6 release 112 running Hilfe v3.5 (Incremental Pike Frontend)
> mixed fun = lambda(){ return 1; };
> fun()[""];
Indexing the integer 1 with unknown method "".
HilfeInput:1: HilfeInput()->___HilfeWrapper()
>
