That would be very awkward:

user=> (-> (range) (filter even?) (drop 10) (take 5))
LazySeq
user=> (-> (range) (filter even?) (drop 10) (take 5) first)
20
user=> (-> (range) (filter even?) (drop 10) (take 5) second)
22
.......

On Sep 14, 5:20 am, Ranjit <rjcha...@gmail.com> wrote:
> Thanks for clearing that up for me everyone. So the REPL itself acts
> like a consumer of lazy sequences? Is there some logic behind that? I
> guess I would have expected that the REPL would just return a
> reference to a lazy expression rather than evaluate it.
>
> Thanks,
>
> -Ranjit
>
> On Sep 13, 2:06 pm, Alan <a...@malloys.org> wrote:
>
> > Ranjit, try the following to see it in action even at the REPL:
>
> > (def xt (make-array Float/TYPE 3 3))
>
> > (def myloop (for [x (range 3) y (range 3)] (aset xt x y 1)))
>
> > (aget xt 1 1) ;; xt hasn't been changed
>
> > myloop ;; force REPL to de-lazify
>
> > (aget xt 1 1) ;; changed now
>
> > On Sep 13, 9:28 am, Mark Nutter <manutte...@gmail.com> wrote:
>
> > > Erg, gmail hiccup. Started to say if you try to use it in code that's
> > > *not* being called from the REPL, you'll be scratching your head
> > > trying to figure out why aset never gets called.
>
> > > Mark
>
> > > On Mon, Sep 13, 2010 at 12:27 PM, Mark Nutter <manutte...@gmail.com> 
> > > wrote:
> > > > The REPL automatically realizes the lazy sequence in the process of
> > > > printing it out, but if you try to us
>
> > > > On Mon, Sep 13, 2010 at 11:07 AM, Ranjit <rjcha...@gmail.com> wrote:
> > > >> Thanks Armando for catching my stupid mistake. That fixed everything.
>
> > > >> Meikel, I'm not sure I understand what you're saying. When I evaluate
> > > >> this in the REPL
>
> > > >> (for [x (range 2) y (range 2)] (aset xt x y (+ x y)))
> > > >> (aget xt 0 0)
> > > >> (aget xt 1 1)
>
> > > >> I get back 0 and 2 as I expect. Isn't the call to aset consuming the
> > > >> lazy sequence?
>
> > > >> Thanks.
>
> > > >> On Sep 13, 11:00 am, Meikel Brandmeyer <m...@kotka.de> wrote:
> > > >>> Hi,
>
> > > >>> On 13 Sep., 15:07, Ranjit Chacko <rjcha...@gmail.com> wrote:
>
> > > >>> >     (for [x (range 3) y (range 3)] (aset xt x y 1))
>
> > > >>> Note that that this will not do what you think it does. for creates a
> > > >>> lazy sequence which is thrown away immediately. So the aset calls are
> > > >>> never done. for is a list comprehension, not a looping construct.
> > > >>> Replace for with doseq. As a rule of thumb: side-effects => command
> > > >>> starting in "do".
>
> > > >>> Sincerely
> > > >>> Meikel
>
> > > >> --
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>
>

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