Provides classes that implements the Jif AST node extensions and delegates.

All the extensions extend from the class {@link jif.ast.Jif_c Jif_c} and implement the labelCheck method. All delegates extend the class {@link jif.extension.JifJL_c JifJL_c}. @see polyglot.ast.Ext @see jif.ast.Jif @see jif.ast.Jif_c @see jif.extension.JifStmtExt