[Discuss-gnuradio] Emergent code-generation weirdness in GRC

[Marcus D. Leech]

I just had a weird problem with multimode.py with a user bringing it up 
on Ubuntu.

It provoke TypeErrors in the multiply_const blocks, due to 
multipy_const_vxx expecting a vector, and being passed a scalar.

GRC has code in it to recognize scalars, and wrap "[ ]" around them to 
make them lists, and thus "correct" types for multiply_const_vxx.

Except that this "recognizer" now appears to be broken on some 
platforms, and not others, so even when I'm using a multiply_const block
  (from GRC) for a non-vector flow, I have to wrap my constants (which 
are in turn in variables) inside "[" "]".  This has worked for
  years and years.  Otherwise, things like GUI slider controls attached 
to multiply_const blocks wouldn't work, but they do, because
  the evaluator inside GRC recognizes the scalar type and "does the 
right thing".  Except, now, it's not always "doing the right thing".
  I'm seriously puzzled.

I saw an instance of this a couple of months ago, but never tracked it 
down to anything.  The "victim" user today was using the very-latest
  "maint" (3.6.5) on Ubuntu 13.04, as I recall.

Josh has already seen this, but if anyone else has any ideas, 
particuarly about why on one platform and not another, that would be good.

--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org