message: sv2017: rm ambiguity between nonblocking_assignment and expr
diff: @@ -483,7 +483,8 @@ statement_item:
  ( blocking_assignment
  | nonblocking_assignment
  | procedural_continuous_assignment
  - | expression
  + | inc_or_dec_expression
  + | primary
  // | clocking_drive // just a nonblocking_assignment assignment
  ) SEMI #statement_itemSemiEnding
  | case_statement #statement_itemCase
  @@ -938,8 +939,6 @@ property_case_item:
  /****************************************** ids and selects ***********************************************************/
  bit_select:
  LSQUARE_BR expression RSQUARE_BR;
  -clockvar_expression:
  - hierarchical_identifier select;
  package_or_class_scoped_hier_id_with_select:
  package_or_class_scoped_path ( bit_select )* ( DOT identifier ( bit_select )* )* ( LSQUARE_BR
  @@ -1368,13 +1367,16 @@ primary:
  /************************************************** expression ********************************************************/
  constant_expression:
  expression;
  +inc_or_dec_expression:
  + inc_or_dec_operator ( attribute_instance )* variable_lvalue #inc_or_dec_expressionPre
  + | variable_lvalue ( attribute_instance )* inc_or_dec_operator #inc_or_dec_expressionPost
  +;
  expression:
  primary #expressionPrimary
  | LPAREN operator_assignment RPAREN #expressionPar
  | KW_TAGGED identifier ( expression )? #expressionTaged
  | unary_operator ( attribute_instance )* primary #expressionUnary
  - | inc_or_dec_operator ( attribute_instance )* variable_lvalue #expressionIncDecPre
  - | variable_lvalue ( attribute_instance )* inc_or_dec_operator #expressionIncDec
  + | inc_or_dec_expression #expressionIncrDecr
  | expression DOUBLESTAR ( attribute_instance )* expression #expressionPow
  | expression ( MUL
  | DIV
  