anchor.diff:  // Grouped by prioriries: http://php.net/manual/en/language.operators.precedence.php
   // and http://www.phpeveryday.com/articles/PHP-Operators-Operator-Priority-P312.html
   expression
  -    : andOrExpression
  -    | expression QuestionMark expression? ':' andOrExpression
  -    | expression LogicalAnd andOrExpression
  -    | expression LogicalXor andOrExpression
  -    | expression LogicalOr andOrExpression
  -    ;
  -
  -andOrExpression
  -    : comparisonExpression
  -    | andOrExpression '&' comparisonExpression
  -    | andOrExpression '^' comparisonExpression
  -    | andOrExpression '|' comparisonExpression
  -    | andOrExpression '&&' comparisonExpression
  -    | andOrExpression '||' comparisonExpression
  -    ;
  -    
  -comparisonExpression
  -    : additionExpression
  -    | comparisonExpression ('<<' | '>>') additionExpression
  -    | comparisonExpression (Less | '<=' | Greater | '>=') additionExpression
  -    | comparisonExpression ('===' | '!==' | '==' | IsNotEq) additionExpression
  -    ;
  -
  -additionExpression
  -    : multiplicationExpression
  -    | additionExpression ('+' | '-' | '.') multiplicationExpression
  -    ;
  -
  -multiplicationExpression
  -    : notLeftRecursionExpression
  -    | notLeftRecursionExpression '**' multiplicationExpression
  -    | multiplicationExpression InstanceOf typeRef
  -    | multiplicationExpression ('*' | Divide | '%') notLeftRecursionExpression
  -    ;
  -
  -notLeftRecursionExpression
       : Clone expression                                         #CloneExpression
       | newExpr                                                  #NewExpression
       
  
positive.code:     | (Require | RequireOnce) expression                       #SpecialWordExpression
  
      | Static? Function '&'? '(' formalParameterList ')' lambdaFunctionUseVars? blockStatement  #LambdaFunctionExpression
      ;
  
  newExpr
  
negative.code: /*
  PHP grammar.
  The MIT License (MIT).
  Copyright (c) 2015-2017, Ivan Kochurkin (kvanttt@gmail.com), Positive Technologies.
  
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  