Re: [myhdl-list] AttributeError in 0.8-dev but not in 0.7

[Jan D. <ja...@ja...>]

On 01/24/2013 03:39 PM, Per Karlsson wrote:
> Yes, I think you're right! It is mixing intbv[1:0] and bool that
> causes it.
>
> If that is to be forbidden, there needs to be an assert as soon as
> possible. But I don't see why we should disallow it. The reason I
> didn't see it sooner was that the bool and the intbv were
> instantiated in separate modules. And unless we ban one-bit intbvs or
> bools outright

I don't see what you mean here. You could just use intbv[0] to
assign to a boolean Signal.

  I don't see how that sort of thing can be avoided. One
> hardware designer's bool is another's one bit integer. :) /Per

We are talking about intbv versus bool. Intbv also has a "bit-vector"
meaning. To me, a bit-vector with a width 1 is just a degenerated
vector, not the same as a single bit variable/signal. In VHDL it is
also like that - therefore if we start changing this there will be
all kinds of tricky issues after conversion.

For single bit variables/Signal, the idiomatic MyHDL way is bool,
not intbv[1:0], which looks like a user error to me.
I agree that there is should be a direct error check to prevent assigning
an intbv[1:0] to a bool Signal however, so that the issue if
flagged early on.

Jan

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