Hello, I am currently working on a Python script in Rhino and have encountered an error that I am unable to resolve. The error message is as follows: TypeError: an integer is required in method Void .ctor(Int32) This error occurs when I attempt to create a polyline using the rs.AddPolyline method…

Can you share the script and the conditions under which the error occurs?

Hi @Guillec , Looking at that specific call in the API docs: RhinoScriptSyntax AddPolyline(points, replace_id=None) I don’t think it would return that TypeError so its likely that the TypeError is coming from after your AddPolyline call or from what you are d…

Hello, I apologize for not providing context earlier. Here is a script where the error occurs. This error appears in several of my scripts that previously worked perfectly, and I haven’t changed anything in these scripts. Even more strangely, the error appears in certain Rhino files but not in all …

Do you have a .3dm file we can test with that produces the error? Do you have the line number on which it happens?

Try calling rs.AddPolyline on a list of lists (of the vertices’ co-ordinates).

[image] Unfortunately, nothing changes even with a very simple script; the problem persists.

That’s a list of points, not a list of lists of co-ordinates. Try: point = [list(point1),list(point2),list(point3)]

Even the basic code from the Rhyno Syntax website doesn’t work on my PC. [image]

Hmm… well @Guillec< This works perfectly fine for me with IronPython2 and Python 3, Rhino 8.22: #! python 3 import rhinoscriptsyntax as rs points = rs.GetPoints(True) if points: rs.AddPolyline(points) What version are you on? Also since you last updated, have you reset your Python runtime? Add…

I am getting the same error in Grasshopper using the Python 3 component when trying to create a Polyline (it works fine in IronPython 2 component). [Screenshot 2025-10-15 171549] Seems like it is defaulting to the Polyline( int initialCapacity) constructor, rather than Polyline(IEnumerable<Point3…

Bug script python polyline

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Bug script python polyline

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