Owner's Manual (Complete)

Chapter 11 - Expressions
The Home Control Assistant
3
A lot of work went into the Visual Programmer to allow HCA users to create programs without all
the baggage of existing programming languages – careful syntax, programming terms and
concepts. These two elements take a step back from that and leave you in the realm of the
programmer. If you have never used, for example, Visual Basic, or all this sounds Greek to you,
stick with simple yes and no flags managed with the visual programmer elements for them. You
can do many wonderful things with them alone.
Expression builder
To help you create expressions, rather then always having to refer to this documentation, HCA
contains a tool called the Expression Builder.
On dialogs where you enter an expression, a button labeled
Expression Builder helps you compose
your expression. Pressing this button opens this dialog:
The upper left box specifies what sort of item you are inserting. The most common case is one of
the HCA build-in functions.
The box below that lets you limit the number of choices of the possible functions you have to
choose from.
The third section of the dialog changes depending upon what you are inserting. In the picture
above, a function is being inserted. Choose the name of the function in the dropdown and two
things display: a short explanation of what it does, and the parameters to the function. In this
example, the _right function takes two arguments. You can simply type in the two arguments, or to
get more assistance, press the button next to the argument. This opens this dialog: