FlowBoxSortFunc

typealias FlowBoxSortFunc = (child1: FlowBoxChild, child2: FlowBoxChild) -> <Error class: unknown class>(source)

A function to compare two children to determine which should come first.

param child1 the first child
param child2 the second child
return < 0 if @child1 should be before @child2, 0 if they are equal, and 0 otherwise