code: protected AstNode parseSlashedStatement( DdlTokenStream tokens,
                                               String[] stmt_start_phrase,
                                               AstNode parentNode,
                                               String mixinType ) {
          assert tokens != null;
          assert stmt_start_phrase != null && stmt_start_phrase.length > 0;
          assert parentNode != null;
  
          markStartOfStatement(tokens);
          tokens.consume(stmt_start_phrase);
          AstNode result = nodeFactory().node(getStatementTypeName(stmt_start_phrase), parentNode, mixinType);
  
          parseUntilFwdSlash(tokens, false);
  
          consumeSlash(tokens);
  
          markEndOfStatement(tokens, result);
  
          return result;
      }
docs: Utility method to parse a generic statement given a start phrase and statement mixin type.
  
  @param tokens the tokenized {@link DdlTokenStream} of the DDL input content; may not be null
  @param stmt_start_phrase the string array statement start phrase
  @param parentNode the parent {@link AstNode} node; may not be null
  @param mixinType the mixin type of the newly created statement node
  @return the new node