The current built-in > does not resolve its arguments

[andersmurphy]

Openning this as an issue from our slack conversation.

I’m trying to filter for messages that have content longer than 200 characters:

       [?u :message/content ?content]
       [(> (count ?content) 200)]
       :find (count ?content).]
  @*conn*)
  
=> nil

Doesn’t return anything. Why? I’m assuming you can’t nest functions?

Separating out the functions still doesn’t return anything either though:

       [?u :message/content ?content]
       [(count ?content) ?n]
       [(> ?n 200)]
       :find (count ?content).]
       @*conn*)
=> nil    

If I implement my own greater than function this works:

  (> a b))

(d/q '[:where
       [?u :message/content ?content]
       [(count ?content) ?n]
       [(app.scratch/my2> ?n 200)]
       :find  (count ?content).]
       @*conn*)
=> 5       

Is this because > is special for range queries?

• Anders

the current built-in > does not resolve its arguments. Remember, we cannot call eval, so we need to walk the arguments to >
resolve them.

• Huahai

My take away from the conversation is the below should work, but nesting functions can't (as it gets messy with eval).

(d/q '[:where
       [?u :message/content ?content]
       [(count ?content) ?n]
       [(> ?n 200)]
       :find (count ?content).]
       @*conn*)
=> nil      

I'm going to have a look into this and see if I can create a PR.