Python Script Engine  7.0
GL Studio Editor Python Script API
Truth Value Checking

Here is an example of how truth value checking works in this API.

Objects from this API are considered false when:

Python Docs on Truth Value Checking

1 import Editor
2 import Vertex
3 import VertexArray
4 
5 # Opening two documents, one new document, and one that doesn't exist
6 docExists = Editor.NewDocument()
7 nullDoc = Editor.OpenDocument( "nonExistentDoc.gls" )
8 
9 # Will be True because the document object exists
10 if docExists:
11  print "Document exists."
12 
13 # Will be considered False since the object is null
14 if not nullDoc:
15  print 'Document does not exist'
16 
17 # Creating an empty VertexArray
18 vertexArray = VertexArray.VertexArray()
19 
20 # Will be considered False because the array object is empty
21 if not vertexArray:
22  print 'The array is empty'
23 
24 # Adding a vertex to the array
25 vertex = Vertex.Vertex( 0, 0, 0 )
26 vertexArray.Insert( vertex )
27 
28 # Will now be considered True because the array is not empty
29 if vertexArray:
30  print 'The array is not empty'
31 
32 # Retrieving the document's sound list and adding a sound to it
33 soundList = docExists.GetSoundList()
34 soundList.AddSound( "someSound.mp3" )
35 soundItem = soundList.GetSoundItem( 0 )
36 
37 # The SoundItem exists as long as it's in the SoundList
38 if soundItem:
39  print 'This SoundItem exists'
40 
41 # Once the SoundItem is removed, it is considered null, and therefore false
42 soundList.RemoveSound( soundItem )
43 if not soundItem:
44  print 'This SoundItem no longer exists'