[chuck-users] wishlist for the new year
haberg at math.su.se
Mon Jan 11 15:30:49 EST 2010
This may in fact cause problems in ChucK with its heavy overloading of
the Chuck operator not => but perhaps with the new <=.
One would expect
1 => foo => bar;
to bind to the left, as
(1 => foo) => bar;
This will then also work with input streams (not yet implemented in
chin => foo => bar;
should mean: first foo(chin), and pass the return value to bar.
Now reverse this, using <=. If it works like an ordinary assignment,
one should write
bar <= foo <= 1;
and here => should (by common expectation) be binding right:
bar <= (foo <= 1);
First pass 1 to foo, and the result to bar.
But for output streams, it should bind to the left:
chout <= foo <= bar;
(chout <= foo) <= bar;
First pass chout to foo, and the pass the result to bar.
On streams, there is no semantic difference between => and <=; they
are just used as eye-candy to show the difference between input and
But for assignments, there is a difference in binding to the left and
to the right.
On 11 Jan 2010, at 19:19, mike clemow wrote:
> No, you're not misunderstanding anything! I got a little
> confused... you can do two things with chaining in chuck. one is a
> double-assignment (which is what I thought was happening):
> 1 => int i => int j;
> the other is passing args to functions:
> fun int foo(int i)
> return i+1;
> 1 => foo; // returns 2
> but, if we did like you suggested:
> fun void bar(int b)
> <<< "hi", b >>>;
> then this:
> 1 => foo => bar;
> will print "hi 2". but what i was missing was the fact that 1 =>
> foo returns 2 and passes that to bar. which is different from the
> double assignment. if foo didn't return an int, the above wouldn't
> be possible.
> for instance, if foo was changed to this:
> fun void foo(int i)
> //return i+1;
> <<< i >>>;
> then the line
> 1 => foo => bar;
> would fail with this error:
> [Untitled 2]:line(12): argument type(s) do not match:
> [Untitled 2]:line(12): ... for function 'bar(...)' ...
> [Untitled 2]:line(12): ...(please check the argument types)
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