using hou.Node.destroy()

[JJM]

Hi!

How to use Node.destroy() method?

If we define something like this:

def delSearch(patt):
    for n in hou.node('/obj/').allSubChildren():
        if n.name().startswith(patt):
            print (n.path())
            n.destroy()

Then call it:

hou.session.delSearch("rozo")

Houdini prints one node name and removes this node. But then reports error:

>>> hou.session.delSearch("rozo")
/obj/rozok26
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "hou.session", line 3, in delSearch
  File "/opt/hfs15.0.347/houdini/python2.7libs/hou.py", line 5140, in name
    return _hou.Node_name(*args)
ObjectWasDeleted: Attempt to access an object that no longer exists in Houdini.

What can i do to delete all nodes with same name pattern?

This case is described in documentation but i can't find a way to resolve this problem.

 

 

 

 

[Atom]

Maybe it is because you are modifying the list you are iterating over?

 

Instead of deleting inside the loop, consider collecting names to delete in a second pass.

def delSearch(patt):
    results = []
    for n in hou.node('/obj/').allSubChildren():
        if n.name().startswith(patt):
            print (n.path())
            results.append(n.path())
 
     if len(results):
        for node_name in results:
            hou.node(node_name).destroy()
 
hou.session.delSearch("rozo")

Edited February 29, 2016 by Atom

[JJM]

it's doesn't work.

def delSearch(patt):
    results = []
    for n in hou.node('/obj/').allSubChildren():
        if n.name().startswith(patt):
            print (n.path())
            results.append(n.path())
    print (len(results))            
    if len(results):
        for node_name in results:
            hou.node(node_name).destroy()

output:

hou.session.delSearch("Arch")
/obj/Arch41_052_obj_20
.....
/obj/Arch41_052_obj_7
/obj/Arch41_052_obj_7/Arch41_052_obj_7
/obj/Arch41_052_obj_19
/obj/Arch41_052_obj_19/Arch41_052_obj_19
30

Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "hou.session", line 11, in delSearch
AttributeError: 'function' object has no attribute 'destroy'

something wrong...

Edited February 29, 2016 by JJM

[lukeiamyourfather]

Is it deleting the parent and then can't find the child? It looks like there are children with the same pattern in their name. The proper way if that's the case would be to get a new list of nodes each time one is deleted until none are left (while loop).

[michael]

if you have 

/obj/Arch41_052_obj_20
.....
/obj/Arch41_052_obj_7

 

don't use subChildren() - that will search recursively through the entire file

and find things like /obj/Arch41_052_obj_7/Arch41_052_obj_7

just use 

for child in node.children()

that will get all the nodes at the /obj/ level

/obj/Arch41_052_obj_7 etc

[JJM]

Thanks for the help.
this code works fine:

def delSearch(patt):    
    results = []
    for n in hou.node('/obj/').children():
        if n.name().startswith(patt):
            print (n.path())
            results.append(n.path())
     
    print (len(results))            
    if len(results):
        for node_name in results:
            hou.node(node_name).destroy()

Edited March 1, 2016 by JJM