Why does LabVIEW allow me to have 2 controls with same name

Question

Here's a general LabVIEW question:
Why does LabVIEW allow me to have 2 controls with the same name in the same VI?  It seems like this only increases the chances of confusion.  Especially when someone is just looking at a block diagram (or documentation of a block diagram).
No other programming language that I know of allows this.  I realize that uniqueness of name is not as critical in LabVIEW as it is in any text based language.  For example, in a text based language, if I had 2 variables called abc and I wrote a statement
abc = 12;
the compiler would not know which abc was being referred to.  In LabVIEW, if we had 2 controls called abc, the equivalent of doing an abc=12 is writing to a local variable (which is always linked to one of the controls) and there is no ambiguity.  Still, someone looking at the code cannot figure out which abc is linked to unless he does a right click>>Find>>terminal (or a double click).
Even though I have never and never will name 2 controls the same, I think it would be a nice constraint to see enforced by LabVIEW.
Any input from NI engineers on this?
Message Edited by S G on 12-18-2007 03:38 PM
S G
Certified LabVIEW Architect, Certified TestStand Developer, Certified Professional Instructor
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Answer 1

I know when you copy and paste a control or indicator, LabVIEW automatically increments the label. But since you can hide the label, and show or hide the caption, there must be another mechanism that LabVIEW uses to keep track of all the controls. I thought I remember back in the "old days" (ver 6 or 6i) LabVIEW would give you an error if you tried to make two controls with the same name. Perhaps that was LabWindows/CVI.
I don't know where the index is actually stored, but if you look at a property node linked to the Pane, you will see an array of references to the controls and indicators. Since the references are stored in an array, I assume that any local variables are tied to the index of that array. Since the labels themselves are properties of the control, I guess there's no reason to limit what that label is. They all have a unique index number.
Interestingly, this array of references grows from the beginning. That is, any new control or indicator is put at index 0, not the end of the array.
B-)
Message Edited by LabViewGuruWannabe on 12-18-2007 08:45 PM
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