Problem using for each in subform

Problem using for each in subform

I have a subform in one of my forms, and sometimes I have to use a for each statement in this subform. Now, my problem is, I've seen it suggested everywhere that the syntax is supposed to be: 

for each var in SubformField

Every time I tried this doesn't work for me, so I have to use:

for each var in input.SubformField

It isn't exactly a problem, but, let's say it's on the 'on user input' action of one of my fields, if I need to edit this action for any reason, when I click on it, it removes the input on my statement  automatically, thus my application doesn't work correctly, launching some kind of error. 

How can I fix this? It really doesn't work without the input and I can't simply expect that if someone else has to edit my application, that they'll know how to fix this issue.