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--- jas:breakpoints [2010/01/04 23:32] – created jwarrior
+++ jas:breakpoints [Unknown date] (current) – external edit (Unknown date) 127.0.0.1
@@ Line 1: / Line 1: @@
+===== Break Points =====
+Break points can be set in Smalltalk methods to force sim execution to stop so that you can see what is going on.
+Here are some useful ways to set break points:
+<code>
+JwServices currentTime > 23.67
+</code>
+This break point will stop execution in the method when the sim time is greater than 23.67.
+<code>
+bseId = #'BLUE_AIRPLANE'
+</code>
+This break point will stop execution in the method when the bseId = the symbol #BLUE_AIRPLANE. Symbols with underscores must be entered using single quotes. All subclasses of BattleSpaceEntity respond to the message bseId.
+You can set a break point on any condition or variable, including method temporary variables, that is 'visible' (exists) in the method.
+<code smalltalk>
+someMethod
+| flightTime |
+flightTime := 0.
+bseId = #'BLUE_AIRPLANE'
+    ifTrue: [flightTime := 3]
+^flightTime
+</code>
+You could set a break point on the temporary variable flightTime like this:
+<code>
+flightTime = 3
+</code>
+or
+<code>flightTime > 2</code>
+ on the line ^flightTime to stop execution.
+To see what instance variables a method understands, browse the class that owns the method, and then select 'Browse References -> To an instance variable' from the right click menu.
+{{:jas:jasbreakpoints.jpg|}}