How to use [filter]

The reference page of filter has its arguments, constraints and declaration.

Filter allows you to filter using a predicate. If the predicate returns true for the currently iterated list item, it’s included, otherwise not. Below is an example.

.src
   .:int:1
   .:int:2
   .:int:3
   .:int:4
filter:x:@.src/*
   mt
      get-value:x:@.dp/#
      .:int:2
   return:x:-

The above will return only nodes having a value above integer value “2”.