Infinite Recursion #150

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1. Cabalist commented on Jul 15, 2020

   

   Cabalist

   on Jul 15, 2020

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   You are appending something to itself.

   I think this would cause an exception in any python program.
2. ottojas commented on Jul 16, 2020

   

   ottojas

   on Jul 16, 2020 via email

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   Actually python handles this very well.

   >> k=[5,6.7] >> sum(k)

   11.7 Here is how python handles it.

   >> k.append(k) >> k

   [5, 6.7, [...]]

   >> sum(k)

   Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: unsupported operand type(s) for +: 'float' and 'list' Rather than going into infinite recursion it produces an error. There is a fix. File "/home/otto/.local/lib/python3.7/site-packages/solid/solidpython.py", line 246, in <listcomp> [self.add(c) for c in child] File "/home/otto/.local/lib/python3.7/site-packages/solid/solidpython.py", line 241, in add if isinstance(child, (list, tuple)): The code: if len(child) == 1 and isinstance(child[0], (list, tuple)): child = child[0] [self.add(c) for c in child] Is too promiscuous. The recursion originally occurred accidentally, the appending a list to itself is what was happening deep in code and I created the example specifically to show that this could happen. I don't think this is possible in openscad itself. But maybe I will try to see if I can get a self referential loop going there. I rather doubt it. Solid python is a great program and I am porting a number of my projects to it and want to support it.. But it does still have a few raw edges. Regards Otto

   …

   On Wed, 15 Jul 2020 14:09:35 -0700 Ryan Jarvis ***@***.***> wrote: You are appending something to itself. I think this would cause an exception in any python program.
3. ottojas commented on Jul 22, 2020

   

   ottojas

   on Jul 22, 2020 via email

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   I can't find the issue to post my fix. Here it is: In solidpython.py in the add method, def add(self, child: Union["OpenSCADObject",Sequence["OpenSCADObject"]]) change the last line of: if isinstance(child, (list, tuple)): # __call__ passes us a list inside a tuple, but we only care # about the list, so skip single-member tuples containing lists if len(child) == 1 and isinstance(child[0], (list, tuple)): child = child[0] [self.add(c) for c in child] to two lines: if isinstance(child, (list, tuple)): # __call__ passes us a list inside a tuple, but we only care # about the list, so skip single-member tuples containing lists if len(child) == 1 and isinstance(child[0], (list, tuple)): child = child[0] [self.add(c) for c in child] else: raise TypeError("unsupported operand type(s) for +: 'solid.object' and 'list'") Which causes solid to treat it in the same manner as python and throw an error rather than an infinite recursion. Regards Otto

   …

   Actually python handles this very well. >>> k=[5,6.7] >>> sum(k) 11.7 Here is how python handles it. >>> k.append(k) >>> k [5, 6.7, [...]] >>> sum(k) Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: unsupported operand type(s) for +: 'float' and 'list' Rather than going into infinite recursion it produces an error. There is a fix. File "/home/otto/.local/lib/python3.7/site-packages/solid/solidpython.py", line 246, in <listcomp> [self.add(c) for c in child] File "/home/otto/.local/lib/python3.7/site-packages/solid/solidpython.py", line 241, in add if isinstance(child, (list, tuple)): The code: if len(child) == 1 and isinstance(child[0], (list, tuple)): child = child[0] [self.add(c) for c in child] Is too promiscuous. The recursion originally occurred accidentally, the appending a list to itself is what was happening deep in code and I created the example specifically to show that this could happen. I don't think this is possible in openscad itself. But maybe I will try to see if I can get a self referential loop going there. I rather doubt it. Solid python is a great program and I am porting a number of my projects to it and want to support it.. But it does still have a few raw edges. Regards Otto On Wed, 15 Jul 2020 14:09:35 -0700 Ryan Jarvis ***@***.***> wrote: > You are appending something to itself. > > I think this would cause an exception in any python program. >
4. ottojas commented on Jul 22, 2020

   

   ottojas

   on Jul 22, 2020 via email

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   Please ignore previous letter. I will go through the draconian github technique for submitting bugs next time. Fix doesn't work, it breaks other parts. Regards Otto I can't find the issue to post my fix. Here it is: In solidpython.py in the add method, def add(self, child: Union["OpenSCADObject",Sequence["OpenSCADObject"]]) change the last line of: if isinstance(child, (list, tuple)): # __call__ passes us a list inside a tuple, but we only care # about the list, so skip single-member tuples containing lists if len(child) == 1 and isinstance(child[0], (list, tuple)): child = child[0] [self.add(c) for c in child] to two lines: if isinstance(child, (list, tuple)): # __call__ passes us a list inside a tuple, but we only care # about the list, so skip single-member tuples containing lists if len(child) == 1 and isinstance(child[0], (list, tuple)): child = child[0] [self.add(c) for c in child] else: raise TypeError("unsupported operand type(s) for +: 'solid.object' and 'list'") Which causes solid to treat it in the same manner as python and throw an error rather than an infinite recursion. Regards Otto

   …

   Actually python handles this very well. >>> k=[5,6.7] >>> sum(k) 11.7 Here is how python handles it. >>> k.append(k) >>> k [5, 6.7, [...]] >>> sum(k) Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: unsupported operand type(s) for +: 'float' and 'list' Rather than going into infinite recursion it produces an error. There is a fix. File "/home/otto/.local/lib/python3.7/site-packages/solid/solidpython.py", line 246, in <listcomp> [self.add(c) for c in child] File "/home/otto/.local/lib/python3.7/site-packages/solid/solidpython.py", line 241, in add if isinstance(child, (list, tuple)): The code: if len(child) == 1 and isinstance(child[0], (list, tuple)): child = child[0] [self.add(c) for c in child] Is too promiscuous. The recursion originally occurred accidentally, the appending a list to itself is what was happening deep in code and I created the example specifically to show that this could happen. I don't think this is possible in openscad itself. But maybe I will try to see if I can get a self referential loop going there. I rather doubt it. Solid python is a great program and I am porting a number of my projects to it and want to support it.. But it does still have a few raw edges. Regards Otto On Wed, 15 Jul 2020 14:09:35 -0700 Ryan Jarvis ***@***.***> wrote: > You are appending something to itself. > > I think this would cause an exception in any python program. >