Adding new Input can sometimes break the procedure execution

I didn’t really know how to word the title of this bug.

Here’s the situation.

I have a recursive graph to which I added a new input. In this case a String Input.

This causes the graph to stop executing in Unreal (which I wouldn’t expect since the input is not doing anything, or is not connected to anything.


Note that the new String Input Param is greyed out and can’t be edited. I only manage to edit it after adding a constant and plugging it into it, after disconnecting the input was re-enabled, and the graph resumed to work.


I assume that the greyed-out value is “null” or something. which causes the nested procedure in the recursive loop to not execute. the only way to fix it is to ensure that that value isn’t “null”

It’s not just strings, Any new inputs will cause the same problem.

I have a bug with similar symptoms, but it’s when you delete inputs from procedures that are in use. How are you adding the input?

Right-clicking the Input area / Add Input

You can do that?! I don’t remember adding that :rofl:
I guess that’s broken then. Oops.

Can you try dragging a wire out to make new connections instead for now plz.

UPDATE: Yes, it’s flawed, doesn’t work properly if the procedure is already in use in any procedure.

If I drag from an existing node into the input bar it works fine.

This doesn’t break the graph

This does

The ability to do that, (adding an input beforehand) is really useful for me. because I can start defining from scratch what kind of inputs I will want to have

(e.g. Size, Number of iteration, etc).

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I just ran into the delete input from the procedure bug. Where you need to disconnect the procedure from the nested graph before deleting the input.

Potential workaround: If you save, close, and reopen Unreal it might fix this.

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