☰
asStream
🌌array.asStream
redefines Sequence.asStream:
create a stream of T.
A stream contains mutable state, so it cannot be reused or shared
between threads.
Default implementation uses asList. Heirs must redefine at least
one of asList or asStream.
NYI: we create heap allocated instance of array explicitly, needed while
issue #30 is not fixed. Once issue is fixed, array.this can be used instead.
See idiom40ex.fz for a test case