Not with map, which requires equal-length arguments.
You could do the slightly less ugly:
(map
foo
lst-A
lst-B
(range (length lst-A)))
On Thu, Mar 2, 2017 at 11:14 AM, David Storrs <david.sto...@gmail.com> wrote:
>
>
> On Thu, Mar 2, 2017 at 10:09 AM, Stephen Chang <stch...@ccs.neu.edu> wrote:
>>
>> The in-X forms are sequences, and must be used with the sequence API, ie
>> for/X.
>>
>> map only works with lists, so you could use build-list or range:
>> (map
>> foo
>> lst-A
>> lst-B
>> (range 2))
>>
> Is there a way to do it if I don't know how many items will be in the list?
> What I want is to say "just keep sticking numbers in until one of the lists
> runs out." I could say (range 100000000) but that's ugly.
>
>
>>
>> On Thu, Mar 2, 2017 at 9:55 AM, David Storrs <david.sto...@gmail.com>
>> wrote:
>> > I'd like to be able to do something like this:
>> >
>> > (struct foo (a b c))
>> > (define lst-A '(a b))
>> > (define lst-B '(d e))
>> > (map
>> > foo
>> > lst-A
>> > lst-B
>> > (in-naturals))
>> >
>> > I'd expected this to produce: (foo 'a 'd 0) (foo 'b 'e 1), but instead
>> > it
>> > throws an exception "expected list, given stream". I could do it with a
>> > for/list but that's much more verbose. What would be the idiomatic way
>> > of
>> > doing this?
>> >
>> > --
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>
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