GDL Arbitrary Value Contexts
An arbitrary value context is used to define values that contain any arbitrary sequence of characters even if they violate the GDL syntax rules.
The arbitrary value context is introduced when the "<BeginValue:symbol>" character sequence is encountered and terminates when the "<EndValue:symbol>" character sequence is encountered. symbol is any valid symbol token that you choose. The same symbol must appear in both the BeginValue and EndValue invocation. No whitespaces can appear in the BeginValue and EndValue tags.
An arbitrary value context can be defined in any value context except within a comment or a quoted string. The arbitrary value context can appear within a nested context. No contexts are recognized within the arbitrary value context, but any sequence of bytes can be defined within.
An arbitrary value context symbol is a token that consists of characters from the set [A-Z, a-z, 0-9, _ ]. There is no limit to the length of a symbol.