I hope this will be helpful for beginners:
you have 2 or more objects and you want to sort them with sort function.
Here how you do this,
o: context [name: "def"]
p: context [name: "abc"]
k: context [name: "bae"]
and you compare function,
f: func [x y] [x/name < y/name]
you can try this,
f o p
>> false
f p k
>> true
and the last step,
d: sort/compare reduce [o p k] :f
d will be (will point to) [p k o] which is the sorted objects.