Thanks, Juan.

I don't need to know the length of the seq, though, only that it is lazy. I 
don't want to realize *any* lazy seqs. Ideally, I'd like to be able to 
print any data structure and have all lazy seqs print just like it does in 
the example I gave above (i.e., "clojure.lang.LazySeq@c5d38b66"), whether 
it is finite or infinite.

I also don't want to walk through every data structure to check if it 
contains a lazy seq, but maybe that is the only option.

I've also tried:

(defmethod print-method clojure.lang.LazySeq [q, w]
     (.write w "#clojure.lang.LazySeq"))

The next step might be to investigate why infinite lazy seqs don't print as 
clojure.lang.LazySeq, like the finite ones.
On Monday, November 2, 2020 at 9:22:58 AM UTC-8 jpmon...@gmail.com wrote:

> Hi Austin,
>
> Since there is no way to know the length of a lazy-seq without realizing 
> it, I think your only choice is to set a limit on it by binding 
> *print-length* if you are not sure about the sequence. 
>
> Other thing you can try is bounded-count like this :
>
> (defn looks-finite? [xs]
>   (let [limit 1000]
>     (< (bounded-count limit xs) limit)))
>
> (looks-finite? (map inc (range))) ;; => false
> (looks-finite? (map inc (range 100))) ;; => true
>
> I hope that helps.
>
> Juan
> El domingo, 1 de noviembre de 2020 a las 20:06:39 UTC-3, Austin Haas 
> escribió:
>
>>
>> How can I make sure that a logging function won't try to realize an 
>> infinite lazy seq that could be anywhere in the arguments passed to the 
>> logging function?
>>
>> Is there some way to guarantee that lazy seqs won't be realized when 
>> converting to a string?
>>
>> I know I can bind *print-length*, but I don't want to constrain every 
>> collection.
>>
>> And I know that lazy seqs aren't always realized, but that doesn't seem 
>> to help if they are infinite:
>>
>> user=> (str (map inc (range 10)))
>> "clojure.lang.LazySeq@c5d38b66"
>>
>> user=> (str (map inc (range)))
>> <never ends>
>>
>> Thanks.
>>
>>

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