Hans-Peter Diettrich schrieb:
Now I started another branch, that is not as "intrusive" as my other branches. The AltParser branch makes multiple parsers available, each of which sits in its own class derived from TParser.
After some tries I've arrived at a working model. The semantic actions, implemented in semantic objects of various kinds, are currently structured according to their occurence in the parser code. In a later step they should be broken down into logical steps, that better reflect the *needs* of an parser (registering encountered variables...).
Some parser methods have been virtualized, so that existing code can be reused. E.g. calls to statement() or expr() are caught in a procedure, that defers the call to the according virtual method of the current parser. The original reusable procedures have been renamed, so that all calls are routed through the parser methods. Inside an parser the specific procedures can be called directly, bypassing the virtualization.
Now it should be possible to implement a modified OPL syntax, e.g. with modulaic statement sequences instead of statement blocks, block-local variables, initialized local variables, statement sequences separated by commas (C style) and whatever comes into mind. Feel free to implement your own language, based on your TParser descendant in the AltParser branch :-)
Further development should be synced better with the trunk. Please let me know about the chances, that the required hooks are merged into the trunk. When the semantic code is already separated in the general parser units, as demonstrated in the cloned p*OPL units, that code could be maintained in fully reusable semantic objects; these objects can become part of the existing parser units, so that no clones have to be maintained further.
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