Operator symbol for "nb_intdivide"

[Bernhard Herzog]

Guido van Rossum <guido at zope.com> writes:

> > > I don't believe this.  If you can't distinguish / from //, you need
> > > new glasses. :-)
> > 
> > Hmmmm.  Not sure I believe this; mistaking "|" for "||" is said to be
> > a frequent cause of errors in C code.
> 
> For different reasons: they have different priorities but their
> meaning is related (both are "or", just one is bitwise and the other
> is Boolean shortcut).  Programmers coming from languages where only
> "|" existed were tempted to use that, but the priorities are so broken
> that a==b | c==d is parsed as (a == (b|c)) == d.

Interesting that even a language designer with lots of C-experience can
get this wrong :) | has in fact almost the same precedence as || and
it's in fact lower than the comparison operators, so that a==b | c==d is
actually parsed as the user expected ( (a == b) | (c == d)) so it even
works as expected, although in cases where the operands are e.g. a
normal int and a comparison this is likely to break down.

The problem with |'s and &'s precedence in C is that in an expressions
like 0x0f == a & 0x0f, which seems to test whether the 4 lower bits of a
are 1, is in fact parsed as (0x0f == a) & 0x0f.

  Bernhard

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