[Haskell-cafe] Stack Overflow?

[Ben Christy]

I have implemented a scene graph in Haskell and I have a problem. I walk
down the scenegraph and at each node I recalculate translation matrix and
pass it to each child. Well it seems to be causing a stack overflow and I am
lost as to how to resolve the issue without issue a state variable of some
kind to hold a "matrix stack" as is common in imperative implementations of
scene graphs. When I run the program fromghci I get
"drawingcamera"
"drawingground"
"drawinggroundModel"
Matrix4x4 {i1j1 = -4.371139e-8, i1j2 = 0.0, i1j3 = 1.0, i1j4 = -3.9999998,
i2j1
= 0.0, i2j2 = 1.0, i2j3 = 0.0, i2j4 = -1.5, i3j1 = -1.0, i3j2 = 0.0, i3j3 =
-4.3
71139e-8, i3j4 = 3.0, i4j1 = 0.0, i4j2 = 0.0, i4j3 = 0.0, i4j4 = 1.0}
"a model"
"classic matrix operation"
"drawingcarousel"
"drawingcarouselbase"
"drawingcarouselbaseModel"
Matrix4x4 {i1j1 = -4.371139e-8, i1j2 = 1.0, i1j3 = -4.371139e-8, i1j4 = 0.0,
i2j
1 = 0.0, i2j2 = -4.371139e-8, i2j3 = -1.0, i2j4 = 0.0, i3j1 = -1.0, i3j2 =
-4.37
1139e-8, i3j3 = 1.9106855e-15, i3j4 = -1.0, i4j1 = 0.0, i4j2 = 0.0, i4j3 =
0.0,
i4j4 = 1.0}
"classic matrix operation"
"drawingcarouselRoof"
"drawingcarouselRoofModel"
Matrix4x4 {i1j1 = -4.371139e-8, i1j2 = 1.0, i1j3 = -4.371139e-8, i1j4 = 0.0,
i2j
1 = 0.0, i2j2 = -4.371139e-8, i2j3 = -1.0, i2j4 = 0.3, i3j1 = -1.0, i3j2 =
-4.37
1139e-8, i3j3 = 1.9106855e-15, i3j4 = -1.0, i4j1 = 0.0, i4j2 = 0.0, i4j3 =
0.0,
i4j4 = 1.0}
"classic matrix operation"
"drawingcarouselFloor"
"drawingcarouselFloorModel"
Matrix4x4 {i1j1 = -4.371139e-8, i1j2 = 1.0, i1j3 = -4.371139e-8, i1j4 = 0.0,
i2j
1 = 0.0, i2j2 = -4.371139e-8, i2j3 = -1.0, i2j4 = 0.0, i3j1 = -1.0, i3j2 =
-4.37
1139e-8, i3j3 = 1.9106855e-15, i3j4 = -1.0, i4j1 = 0.0, i4j2 = 0.0, i4j3 =
0.0,
i4j4 = 1.0}
"classic matrix operation"
"drawingpolls"
"drawingpoll1"
"drawingpoll1Model"
Matrix4x4 {i1j1 = <interactive>: <<loop>>
<interactive>: interrupted

As you can see there are only a handful of nodes at this point so I am
confused as to why it is happening here, any thoughts?
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