HDevelop User's Manual

36 CHAPTER 2. GRAPHICAL USER INTERFACE
of a program segment (henceforth named body) dependent on a test ( and Ð×)and
the repetition of a program segment (ÓÖ and ÛÐ). Furthermore, you may stop the
program’s execution at any position (×ØÓÔ) or terminate HDevelop (ÜØ). The operators
××Ò and Ò×ÖØ do not influence the execution. They rather serve to specify values
for control data (assignment). The operator ÓÑÑÒØ is used to add a comment, that
means any sequence of characters, to the program. The corresponding menu is shown in
figure 2.22.
Figure 2.22: Menu item ÓÒØÖÓÐ.
Selecting a menu item displays the corresponding control construct in the operator window,
where you can set the necessary parameters. After specifying all parameters you
may transfer the construct into your program. A direct execution for loops and conditions
is not possible, in contrast to other HDevelop and HALCON operators, because you have
to specify the loop’s and condition’s body first to obtain useful semantics. If necessary,
you may execute the program after the input with ËØÔ or ÊÙÒ. The insertion cursor is
positioned after the construct head to ensure the input of the construct’s body occurs in
the correct place. This body is indented to make the nesting level of the control constructs
visible, and thus to help you in understanding the program structure (see figure 2.23). To
get an idea how to use loops, you may look at the example session in section 1.2, and
at the programs in chapters 5.3, 5.8 and 5.9. The semantics for loops and conditions are
shown in chapter 3.7.
The operator ××Ò serves as an assignment operator for control variables (numbers
and strings). Analogously to “normal” operators the input is made in the operator window
by specifying both “parameters” ÁÒÔÙØ and Ê×ÙÐØ (i.e., right and left side of the
assignment). An instruction in C, e.g.,
Ü Ý · Þ
HDevelop / 2000-11-16