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A.2.12 Front End Files
Notebook files as well as front end initialization files can contain a subset of standard Mathematica language syntax. This syntax includes:
Any Mathematica expression in FullForm.
Lists in ... form. The operators ->, :> and &. Function slots in # form.
Special characters in \[Name], \:xxxx or \.xx form.
String representation of boxes involving \(, \) and other backslash operators.
Mathematica comments delimited by (* and *).