public override ASTNode VisitAssignment([NotNull] p4Parser.AssignmentContext context)
{
IdAstNode id = new IdAstNode(context.Id().Symbol, SALTypeEnum.undefined);
Antlr4.Runtime.IToken symbol = Visit(context.assnOp()).Token;
ASTNode expr = Visit(context.expr());
return(new AssignAstNode(id, symbol, expr));
}