Getting it right is however worth the effort, for the sake of both the metamodeler
and modeler. Two of the most common criticisms of tools without a symbol editor are
the lack of freedom in de?¬?ning symbols using the facilities offered, and the massive
amount of time it takes to program the display of such symbols by hand. Even with a
symbol editor, signi?¬?cantly more time is spent building the symbols than building the
abstract syntax of the metamodel: concepts will always be simpler to handle than
representations.
Without a symbol editor, the amount of time required to de?¬?ne symbols will often
approach the ridiculous. For instance, Eclipse??™s GEF comes with a simple example
modeling language for logic circuits: AND, OR and so on. The code for the editor
comes to over 10,000 lines, mostly for the graphical symbols. For the average Java
programmer, that represents a little over one man-year of work. In MetaEdit+,
implementing the same language took just one hour: over 2000 times faster. Even an
author of the IBM Redbook on EMF and GEF (Moore et al., 2004), Anna Gerber,
accepted the difference of roughly three orders of magnitude, although she would
expect the actual ?¬?gure to be 600??“700. Mind you, she is probably faster than the
average Java programmer!
Some tools have tried offering a limited range of preprogrammed symbols,
con?¬?gurable by size, color, and so on.
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