When packages have parameters, you can say that an operation is or is not conditional exported depending on the values of those parameters. When the domain of objects has an < operation, we can supply one-argument versions of and which use this operation for sorting. The presence of the operation < is guaranteed when is an ordered set.
In addition to exporting the one-argument sort operations sort:bubble conditionally, we must provide conditional definitions for the sort:insertion operations in the Implementation part. This is easy: just have the one-argument functions call the corresponding two-argument functions with the operation < from .
In ugUserBlocks , we give an alternative definition of bubbleSort using firstfirstList and restrestList that is more efficient for a list (for which access to any element requires traversing the list from its first node). To implement a more efficient algorithm for lists, we need the operation setelt which allows us to destructively change the first and rest of a list. Using Browse, you find that these operations come from category UnaryRecursiveAggregate. Several aggregate types are unary recursive aggregates including those of List and AssociationList. We provide two different implementations for bubbleSort! and insertionSort!: one for list-like structures, another for array-like structures.
The ordering of definitions is important. The standard definitions come first and then the predicate
is evaluated. If true, the special definitions cover up the standard ones.
Another equivalent way to write the capsule is to use an expression: if