Watch

If a watch is set on a target, the evaluation halts when the evaluation process comes to it.
The kinds of the watch-targets and their setting methods are as follows:

Break-Point

So-called "Break-Point" in many other systems is available also in VITSE.
It can be set on an arbitrary range in the input-port window.

To add or delete a break-point,

1. Select the target area in the source code on the input-port window.
   
2. pop-up menu → "set a break-point" or "unset the break-point"

Watch on an Arbitrary Scheme Object

VITSE can watch an arbitrary Scheme object.

To add or delete a watch on a Scheme object, put or remove a check-mark by clicking in the first column on the corresponding row in the table of the Viivi IDE.

Watch on a procedure-call

VITSE can watch a specific procedure-call as well.

To add or delete a watch on a specific procedure call, put or remove a check-mark by clicking in the first column on the corresponding row in the procedure-call table of the Viivi IDE.

Watch on a binding

VITSE can watch a resulting or a specific binding as well.

To add or delete a watch on a resulting binding, put or remove a check-mark by clicking in the first column on the corresponding row in the user-symbol table of the Viivi IDE.
To add or delete a watch on a specific binding, put or remove a check-mark by clicking in the first column on the corresponding row in the scope table of the Viivi IDE.

Watch on an evaluation-count

VITSE can watch a resulting or a specific evaluation-count as well.

To add or delete a watch on a specific evaluation-count,

1. Choose "Debug" menu on the menu-bar of the controller.
2. Choose "Watch-point on an evaluation-count".