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I want to understand the following effect better (In Mathematica 9) .. Or, maybe, is it a bug?

Running the following line

FullForm[Subscript[α,β_]]

gives as output,

(*Output*)
Subscript[\[Alpha], Pattern[\[Beta], Blank[]]]

But then, when I try to edit the above output, I get some unexpected stuff:

enter image description here

There is some strange spacing at the end, and the front end disagrees with the syntax (as evidenced by the red carat).

How do I understand what's going here?

QuantumDot
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1 Answers1

9

My guess is that since you asked for the full form, Mathematica somehow had to display α as \[Alpha] without it automatically turning into α. This is done by manipulating the underlying box forms, which you can see by inspecting the cell contents:

This modified box structure must be throwing the highlighter off. However, the kernel knows how to evaluate it and gives the right expression for the line with the incorrect highlighting.

rm -rf
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    Probably the front end guys didn't care if the hightlighting worked fine for input cells with the nondefault option ShowSpecialCharacters->False – Rojo Nov 01 '13 at 03:13