Mirror function with different number of items in parent lists

Question

I'm often using the mirror function for list building. In earlier versions you only got a warning if the parent lists have different numbers of items. In v9.12.1 this is not possible anymore and you get an error. I would love to get the old behaviour back, because there are many scenarios where the different length is intended. For example if you want to add some additional members to the mirrored list. Would it be possible to consider this for future versions?

Comments

Just a comment ...

What if the lists did have different sizes, how would you display an item that appeared in one list but not the other?

If I had 10 items in list1 and 15 items in list2, and item 13 was to be displayed / selected, how would we display this item?

I'm just curious.

Sometimes I tend to use the Mirror function, and in similar situations I use Perl, for loops and if-else statements to solve the problem. They all do the job in solving the solution.

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We didn't make any changes to that functionality, so I'm not sure why it is not working in 9.12.1.

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Hi Paul, it's like this: We want to add some new members to the list which don't apply to question 1. It would be possible to add those members to the list of question 1, but then you have those empty members in the variable export of question 1.
It would be also possible with Perl, but the Mirror function was just convenient in this case. I was just curious why it worked (with a warning when uploading) in 9.7.2, but not anymore in 9.12.1.

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Hi Ingo,
If you contact me at ammon@sawtoothsoftware.com I can take a look at your study files and figure out what the exact issue is with the mirror function.