Operations form the basis for most things that can be done to data as it passes through a pipe. They are connected to the appropriate type of a Pipe
instance.
There are several classes of operations:
Assertion: It imposes asserted conditions on the records that fail if they're not met. Assertions are specific to single tuples (that is,
Each
), pipes, and grouped tuples (that is,Every
) pipes. As we shall see later, assertions are special and follow a slightly different set of rules than the other four preceding operations listed.
Using operations is easy. An operation is just a class. They are instantiated as objects using new
, and then are attached to pipes by passing them as parameters when Pipe
is created. Then, the pipe passes tuples to the attached operation where they are processed. The following...