[Discuss-gnuradio] Re: list comprehesnion in variable doesnt work

[feldmaus]

Eric Blossom <eb <at> comsec.com> writes:

> 
> On Sat, May 30, 2009 at 10:55:50AM +0000, feldmaus wrote:
> > Hi All again,
> > 
> > list comprehension doesnt work in variables, for  example:
> > [print(i) for i in range(3)]
> 
> "print" is a statement, not a function.  
> 
> I'd probably use:
> 
>   for i in range(3): print i
> 
> > or
> > variable_2 = file('../../../tabs.dat','w')
> > ([variable_2.write(str(i)) for i in [1,2]] is True) &\
> >                   (variable_2.close() is True)
> > doesnt work.
> 
> ([v2.write(str(i)) for i in [1,2]] is True) and v2.close() is True
> 
> will of course always be False, since [None, None] is not True
> 
> It looks like you are trying to abuse list comprehensions for some kind
> of control flow short cut.  I think of them as an equivalent to the
> "map" builtin, a higher-order function.
> 
> You may want to consider "map" and "reduce" in combination.
> 
Thanks for your answer,

i tried to save some infos, because i can not send a string to the file sink.
However i tried to save to a file AND close this in the next step.
But this doesn't work. I still tried the map function, but doesnt got it
to work. And at least i tried to set up 3 variables in grc to
1.)define a file descriptor
2.)write to the file something
3.)and close the file

the last point doesnt work. I dont know why.
If i insert the close() function manually it works. :-)
But not with grc.
I think there is a problem with the sequence grc set up the variables.
However it doesnt work.

regards markus