mcs/class/System.Data/Mono.Data.SqlExpressions/Expressions.cs

   1 //
   2 // Expressions.cs
   3 //
   4 // Author:
   5 //   Juraj Skripsky (juraj@hotfeet.ch)
   6 //
   7 // (C) 2004 HotFeet GmbH (http://www.hotfeet.ch)
   8 //
   9
  10 //
  11 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System;
  34 using System.Collections;
  35 using System.Data;
  36
  37 namespace Mono.Data.SqlExpressions {
  38         internal interface IExpression {
  39                 object Eval (DataRow row);
  40         }
  41
  42         // abstract base classes
  43         internal abstract class UnaryExpression : IExpression {
  44                 protected IExpression expr;
  45
  46                 public UnaryExpression (IExpression e)
  47                 {
  48                         expr = e;
  49                 }
  50
  51                 abstract public object Eval (DataRow row);
  52         }
  53
  54         internal abstract class BinaryExpression : IExpression {
  55                 protected IExpression expr1, expr2;
  56
  57                 protected BinaryExpression (IExpression e1, IExpression e2)
  58                 {
  59                         expr1 = e1;
  60                         expr2 = e2;
  61                 }
  62
  63                 abstract public object Eval (DataRow row);
  64         }
  65
  66         internal enum Operation {
  67                 AND, OR,
  68                 EQ, NE, LT, LE, GT, GE,
  69                 ADD, SUB, MUL, DIV, MOD
  70         }
  71
  72         internal abstract class BinaryOpExpression : BinaryExpression {
  73                 protected Operation op;
  74
  75                 protected BinaryOpExpression (Operation op, IExpression e1, IExpression e2) : base (e1, e2)
  76                 {
  77                         this.op = op;
  78                 }
  79         }
  80 }