Simple syntax - page 4

There is a concept of "pass-through" where a datum passes through one or more devices on its way to a destination. For example, suppose we have a device called "doubler" which outputs exactly double the number last written to it.

And suppose we have a motor controller on a fan behind a register named "fan". Thus, this code spins the fan at twice the rpm of the temperature:

   thermometer => doubler; 
   doubler => fan

We can use the "pass-through" syntax to write this pair of instructions more naturally, like this:

   thermometer => doubler => fan

This syntax makes it more clear that a datum is being routed from the thermometer to the fan, but passing through the doubler on its way.

In general, we can write this: A => B ; B => C ; C => D ; D => E

like this:                     A => B => C => D => E

Note that this is still four instructions. We are not changing the instructions, just the way we write them.