SystemError : line 1 : error return without exception set

[bentoogood]

I have a case where I am getting back an odd 'error without exception'. in the example eval-ing boo will raise the error, where as I can remove part of the string and the error goes away (foo)

boo = "GafferUI.CompoundEditor( scriptNode, children = ( GafferUI.SplitContainer.Orientation.Horizontal, 0.413288, ( ( GafferUI.SplitContainer.Orientation.Vertical, 0.500514, ( {'tabs': (GafferUI.Viewer( scriptNode ),), 'currentTab': 0}, {'tabs': (GafferUI.NodeGraph( scriptNode ),), 'currentTab': 0} ) ), ( GafferUI.SplitContainer.Orientation.Vertical, 0.194245, ( {'tabs': (GafferUI.NodeEditor( scriptNode ), GafferSceneUI.SceneHierarchy( scriptNode )), 'currentTab': 1}, {'tabs': (GafferUI.ScriptEditor( scriptNode ),), 'currentTab': 0} ) ) ) ) )"

foo = "GafferUI.CompoundEditor( scriptNode, children = ( GafferUI.SplitContainer.Orientation.Horizontal, 0.413288, ( ( GafferUI.SplitContainer.Orientation.Vertical, 0.500514, ( {'tabs': (GafferUI.Viewer( scriptNode ),), 'currentTab': 0}, {'tabs': (GafferUI.NodeGraph( scriptNode ),), 'currentTab': 0} ) ), ( GafferUI.SplitContainer.Orientation.Vertical, 0.194245, ( {'tabs': (GafferUI.NodeEditor( scriptNode ),), 'currentTab': 0}, {'tabs': (GafferUI.ScriptEditor( scriptNode ),), 'currentTab': 0} ) ) ) ) )"

layout = eval(boo)
layout = eval(foo)

[bentoogood]

Required to get all the autogenerated screen grabs working properly.

[johnhaddon]

It seems that this only occurs with PyQt builds, and not PySide builds.

[bentoogood]

Working round this by using the public PySide build to create the documentation screen grabs.

[davidsminor]

aha - you know what? The difference between the two strings is the presence of a GafferSceneUI.SceneHierarchy. If I modify the misbehaving string slightly like so:

eval( """
GafferUI.CompoundEditor(
    scriptNode, children =
    (
        GafferUI.SplitContainer.Orientation.Horizontal, 0.413288,
        (
            (
                GafferUI.SplitContainer.Orientation.Vertical, 0.500514,
                (
                    {'tabs': ()},
                    {'tabs': ()}
                    #{'tabs': (GafferUI.Viewer( scriptNode ),), 'currentTab': 0},
                    #{'tabs': (GafferUI.NodeGraph( scriptNode ),), 'currentTab': 0}
                )
            ),
             (
                GafferUI.SplitContainer.Orientation.Vertical, 0.194245,
                (
                    {'tabs': (GafferUI.NodeEditor( scriptNode ), GafferSceneUI.SceneHierarchy( scriptNode )), 'currentTab': 1},
                    {'tabs': (GafferUI.ScriptEditor( scriptNode ),), 'currentTab': 0}
                )
            )
        )
    )
)
""")

then the exception becomes:

NameError : line 26 : name 'GafferSceneUI' is not defined 

So it could just be that error being reported incorrectly?

[davidsminor]

Also, if I import GafferSceneUI beforehand, I can eval the offending string without any problems

[johnhaddon]

That sounds about right - the only times I've ever seen this "error return without exception set" message, there has been a genuine exception thrown somewhere - but it has been mysteriously turned into the confusing one instead. Like it says above though, I haven't managed to reproduce this using PySide, only PyQt.