Attempting to use array which comes from array being modified?

Development Programming & Scripting C++
1

Hello, Im experiencing an issue where a function takes in an array and returns a modified version of it and stores it back into the array it took in. For some reason this is not allowed, I was wondering if anyone knows why, what im doing wrong, and how to fix this?

The error I get is an assertion failed:

Attempting to use a container element which already comes from the container being modified.

Here is the part of code that does not work:


TArray<FAssetData> FilteredAssetData = GetAllObjectLibraryData();

FilteredAssetData = FilterByTag(FilteredAssetData);

I have tried creating a temporary array that FilterByTag stores its output into then assign the temp array to the FilteredAssetData array but still get the same issue.

I have also tried to store the FilterByTag output to a temp array, empty the FilteredAssetData array, loop through the temp array and add every item in the temp array to the FilteredAssetData array.

I need to do this because the FilteredAssetData array needs to be updated because it will then go through a second and third different filter to get to the final result of all filters applied to the FilteredAssetData.

2

Cpp will not allow you modify an array while you still iterating in it.
You can do what other langues automatically do for you:

create a copy of the array, once loop of changes are done on the copy, assign original = copy.

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3

Ah okay, thank you for the help! Got it working :slight_smile:

I really appreciate your help, the issue was actually in the GetAllObjectLibraryData function. I was using the asset registry function “GetAllAssets”, once I switched it to GetAssets with a filter applied the issue went away. So my guess is the get all assets was not finishing before applying my filter to the array?

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