Differences

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--- howtos:toolcoding:common_history_and_background_checks [2010/09/14 16:32]
marcus.williams
+++ howtos:toolcoding:common_history_and_background_checks [2010/09/20 02:37]
marcus.williams
@@ Line 1: / Line 1: @@
-Many views require that a history be selected (if running in a simulator) and/or a background scenario picked in. In these cases a section of code near the top of the view is used to check that the required history and/or background is in place.
+Many views require that a history be selected (if running in a simulator) and/or a background scenario be picked in. In these cases a section of code near the top of the view - following the object declarations - is used to check that the required history and/or background is in place. If not in place the code advises the user and quits.
 Common code sections are listed below.
 ===== Simulator - history and background required =====
@@ Line 19: / Line 18: @@
 </code>
+FIXME - do we have a best practice on the quit() return code?
+===== Simulator - history required, background optional =====
+<code>
+if $history == false
+	say ("this view must be run with a history")
+	quit (1)
+endif
+integer $index
+if $background == false
+	$index = 2
+else
+	$index = 3
+endif
+</code>
+Note the use of $index for indexing the appropriate view.

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