My terminology may be incorrect, but I have a grammar that needs to accept a set of atoms, minus a small subset of atoms...

Sample Grammar

ReservedWord:    
                       Keyword |
                       FutureReservedWord
    
Keyword:               
                       'break'    | 'else'       | 'new'  

FutureReservedWord: 
                       'abstract' | 'enum'       | 'int'      
                       'short'    | 'interface'  | 'static' 

Identifier:            IdentifierName

IdentifierName:        /[\$_a-zA-Z][\$_a-zA-Z0-9]*/

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The Problem

I actually want the Identifier: production to be something like: 

IdentifierName but not ReservedWord

[download]
meaning that we want all possible words EXCEPT those found in ReservedWord (which can get quite large). I do not believe that this can be done using negative lookahead or <reject>...

Oh mighty gods (and <grinning> semi-gods), is this even possible? If not, hours of work are lost and I shall sob quietly in my dark and damp corner. Any ideas?

In reply to Parse::RecDescent - Excluding a Subset of Atoms From a Production Rule by Incognito

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