While 0 and 1 evaluate to a constant, 0..1 evaluates to two scalars which aren't constants.

That said, for (0..1) doesn't actually use the range operator as an optimization. But the result is the same.

In reply to Re^3: Modification of a read-only value attempted?!? by ikegami
in thread Modification of a read-only value attempted?!? by kikuchiyo

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