public dynamic Visit(CompareExpr expr)
{
var left = (Visit((dynamic)expr.First)) as Operand;
var right = (Visit((dynamic)expr.Second)) as Operand;
switch (expr.Type)
{
case CompareType.Eq:
return(left == right);
case CompareType.NotEq:
return(left != right);
case CompareType.More:
return(left > right);
case CompareType.Less:
return(left < right);
case CompareType.MoreEq:
return(left >= right);
case CompareType.LeesEq:
return(left <= right);
default:
throw new ArgumentOutOfRangeException();
}
}
/// <summary>
/// Visits the compare expression tree
/// </summary>
/// <param name="exp"></param>
public object VisitCompare(CompareExpr exp)
{
_callBackOnNodeStart(exp);
_callBackOnNodeStart(exp.Left);
_callBackOnNodeStart(exp.Right);
return(null);
}
private void Compare(object left, object right, Operator op, bool expected)
{
// LESS THAN
var exp = new CompareExpr(new ConstantExpr(left), op, new ConstantExpr(right));
Assert.AreEqual(expected, exp.EvaluateAs <bool>());
}
public dynamic Visit(CompareExpr expr)
{
var node = Visit((ExpressionBase)expr);
node.Text = expr.Type.ToString();
return(node);
}
/// <summary>
/// Creates a unary expression with symbol scope, context, script refernce set.
/// </summary>
/// <param name="name"></param>
/// <param name="token"></param>
/// <returns></returns>
public static Expr Compare(Expr left, Operator op, Expr right, TokenData token)
{
var exp = new CompareExpr();
exp.Left = left;
exp.Op = op;
exp.Right = right;
SetupContext(exp, token);
return(exp);
}
/// <summary>
/// The shunting yard algorithm that processes a postfix list of expressions/operators.
/// </summary>
/// <param name="context"></param>
/// <param name="parser"></param>
/// <param name="stack"></param>
/// <returns></returns>
public static Expr ProcessShuntingYardList(Context context, Parser parser, List <object> stack)
{
int index = 0;
Expr finalExp = null;
// Shunting yard algorithm handles POSTFIX operations.
while (index < stack.Count && stack.Count > 0)
{
// Keep moving forward to the first operator * - + / && that is found
// This is a postfix algorithm so it works by creating an expression
// from the last 2 items behind an operator.
if (!(stack[index] is TokenData))
{
index++;
continue;
}
// At this point... we hit an operator
// So get the last 2 items on the stack ( they have to be expressions )
// left is 2 behind current position
// right is 1 behind current position
var left = stack[index - 2] as Expr;
var right = stack[index - 1] as Expr;
TokenData tdata = stack[index] as TokenData;
Token top = tdata.Token;
Operator op = Operators.ToOp(top.Text);
Expr exp = null;
if (Operators.IsMath(op))
{
exp = new BinaryExpr(left, op, right);
}
else if (Operators.IsConditional(op))
{
exp = new ConditionExpr(left, op, right);
}
else if (Operators.IsCompare(op))
{
exp = new CompareExpr(left, op, right);
}
exp.Ctx = context;
parser.SetScriptPosition(exp, tdata);
stack.RemoveRange(index - 2, 2);
index = index - 2;
stack[index] = exp;
index++;
}
finalExp = stack[0] as Expr;
return(finalExp);
}
public dynamic Visit(CompareExpr expr)
{
var intdouble = new[] { SymbolType.Double, SymbolType.Integer };
if (intdouble.Contains(expr.FirstType) && intdouble.Contains(expr.SecondType))
{
return(SymbolType.Bool);
}
if (expr.FirstType == expr.SecondType && (expr.Type == CompareType.Eq || expr.Type == CompareType.NotEq))
{
return(SymbolType.Bool);
}
throw new ParseException($"Невозможно сравнить типы {expr.FirstType} и {expr.SecondType}", expr.Node);
}
public dynamic Visit(CompareExpr expr)
{
Visit((ExpressionBase)expr);
if (OptimizeMode.ExpressionSimplify)
{
var left = expr.First as LiteralExpr;
var right = expr.Second as LiteralExpr;
if (left != null && right != null)
{
var literal = new LiteralExpr {
Namespace = expr.Namespace, Node = expr.Node, SymbolType = expr.GetExprType()
};
bool result;
switch (expr.Type)
{
case CompareType.Eq:
result = left.Value == right.Value;
break;
case CompareType.NotEq:
result = left.Value != right.Value;
break;
case CompareType.More:
result = left.Value > right.Value;
break;
case CompareType.Less:
result = left.Value < right.Value;
break;
case CompareType.MoreEq:
result = left.Value >= right.Value;
break;
case CompareType.LeesEq:
result = left.Value <= right.Value;
break;
default:
throw new ArgumentOutOfRangeException();
}
literal.Value = result;
return(literal);
}
}
return(expr);
}
/// <summary>
/// Rule: CompExpr -> AddExpr (COMP AddExpr )? ;
/// </summary>
protected override object EvalCompExpr(ParseTree tree, params object[] paramlist)
{
if (GetNode(TokenType.COMP) == null)
{
return((ExpressionBase)GetNode(TokenType.AddExpr).Eval(tree));
}
var boolExpr = new CompareExpr
{
Node = this,
First = (ExpressionBase)nodes.OfTokenType(TokenType.AddExpr).First().Eval(tree),
Second = (ExpressionBase)nodes.OfTokenType(TokenType.AddExpr).Last().Eval(tree),
OperationText = GetNode(TokenType.COMP).Token.Text
};
return(boolExpr);
}
/// <summary>
/// Evaluate > >= != == less less than
/// </summary>
/// <returns></returns>
public object VisitCompare(CompareExpr expr)
{
var node = expr;
var op = expr.Op;
// TODO: This should be here ( find a better solution )
// e.g. allow expression to support comparable ??
if (expr.Right.Nodetype == NodeTypes.SysAnyOf)
{
var anyOf = ((AnyOfExpr)expr.Right);
anyOf.CompareExpr = expr.Left;
return(this.VisitAnyOf(anyOf));
}
var left = (LObject)expr.Left.Evaluate(this);
var right = (LObject)expr.Right.Evaluate(this);
return(EvalHelper.Compare(node, op, left, right));
}
public static IReadOnlyList<IReadOnlyList<JoinAlias>> ExtractJoinAliases(IFromListItem join)
{
var tree = ExtractJoinAliasTree(join);
var ret = new List<List<JoinAlias>>();
foreach (var level in tree)
{
ret.Add(new List<JoinAlias>());
foreach (var rep in level.Items)
{
if (!ret.SelectMany(x => x).Any(x => x.Find == rep.Find))
{
//Agregar el rep:
var exAlias = ret.SelectMany(x => x).Where(x =>
CompareExpr.ExprEquals(x.Replace, rep.Rep) || CompareExpr.ExprEquals(x.Find, rep.Rep)
).Select(x => x.Alias).FirstOrDefault();
string alias;
if (exAlias != null)
{
alias = exAlias;
}
else
{
var memberAlias = ExtractMemberStr(rep.Rep);
alias = memberAlias;
//Si el alias esta repetido, le ponemos un numero consecutivo
for (var i = 1; i < 1000 && ret.SelectMany(x => x).Where(x => x.Alias == alias).Any(); i++)
{
alias = $"\"{memberAlias.Trim('"') + i}\"";
}
}
ret[ret.Count - 1].Add(new JoinAlias(rep.Find, rep.Rep, alias));
}
}
}
return ret;
}
/// <summary>
/// Remplaza todas las referencias a un elemento del WITH con un SqlTableRefRaw
/// </summary>
public static Expression SubqueryRawSubs(Expression subquery, ParameterExpression repParam)
{
if (subquery == null)
{
return(null);
}
//Sustituir todo param.X o param por el nombre:
var ret = ReplaceVisitor.Replace(subquery, expr =>
{
if (typeof(IFromListItemTarget).GetTypeInfo().IsAssignableFrom(expr.Type.GetTypeInfo()))
{
var selectInt = expr.Type.GetTypeInfo().ImplementedInterfaces.Concat(new[] { expr.Type }).Where(x => x.GetTypeInfo().IsGenericType&& x.GetGenericTypeDefinition() == typeof(IFromListItemTarget <>)).FirstOrDefault();
if (selectInt == null)
{
throw new ArgumentException("Debe de ser un IFromListItemTarget<T>");
}
var selectType = selectInt.GetTypeInfo().GenericTypeArguments[0];
if (expr is MemberExpression mem && CompareExpr.ExprEquals(mem.Expression, repParam))
{
return(RawSqlTableRefExpr(selectType, $"\"{mem.Member.Name}\""));
}
public dynamic Visit(CompareExpr expr)
{
Visit((ExpressionBase)expr);
return(null);
}
/// <summary>
/// Visits the compare expression tree
/// </summary>
/// <param name="exp"></param>
public void Compare(CompareExpr exp)
{
_callBack(exp);
_callBack(exp.Left);
_callBack(exp.Right);
}
/// <summary>
/// run step 123.
/// </summary>
/// <returns></returns>
public override Expr Parse()
{
var startToken = _tokenIt.NextToken;
_tokenIt.ExpectIdText("repeat");
Expr varname = null;
Expr startVal = null;
Expr endVal = null;
Expr incVal = null;
Operator op = Operator.LessThanEqual;
// Case 1: repeat to 10
if (_tokenIt.NextToken.Token.Text == "to")
{
var result = ParseTo();
startVal = new ConstantExpr(1.0);
_parser.SetScriptPosition(startVal, startToken);
op = result.Item1;
endVal = result.Item2;
incVal = result.Item3;
}
// Case 2: repeat 1 to 10
else if (_tokenIt.NextToken.Token.Kind == TokenKind.LiteralNumber)
{
var num = _tokenIt.ExpectNumber();
var result = ParseTo();
startVal = new ConstantExpr(num);
_parser.SetScriptPosition(startVal, startToken);
op = result.Item1;
endVal = result.Item2;
incVal = result.Item3;
}
// Case 3: repeat ndx to 10
else if (_tokenIt.NextToken.Token.Kind == TokenKind.Ident)
{
var variableName = _tokenIt.ExpectId();
varname = new VariableExpr(variableName);
_parser.SetScriptPosition(varname, startToken);
if (_tokenIt.NextToken.Token.Type == TokenTypes.Assignment)
{
_tokenIt.Advance();
// Upto "to"
startVal = ParseExpr(_terminatorForTo);
}
else
{
startVal = new ConstantExpr(0);
_parser.SetScriptPosition(startVal, startToken);
}
var result = ParseTo();
op = result.Item1;
endVal = result.Item2;
incVal = result.Item3;
}
// auto-create variable name.
if (varname == null)
{
varname = new VariableExpr("it");
_parser.SetScriptPosition(varname, startToken);
}
// Now setup the stmts
var ctx = _parser.Context;
var startStmt = new AssignExpr(true, varname, startVal);
_parser.SetScriptPositionFromNode(startStmt, varname);
startStmt.Ctx = ctx;
var condition = new CompareExpr(varname, op, endVal);
_parser.SetScriptPositionFromNode(condition, endVal);
varname.Ctx = ctx;
condition.Ctx = ctx;
var incExp = new UnaryExpr(varname.ToQualifiedName(), incVal, Operator.PlusEqual, _parser.Context);
_parser.SetScriptPositionFromNode(incExp, incVal);
var incStmt = new AssignExpr(false, new VariableExpr(varname.ToQualifiedName()), incExp);
_parser.SetScriptPositionFromNode(incStmt, incExp);
incStmt.Ctx = ctx;
var loopStmt = new ForExpr(startStmt, condition, incStmt);
ParseBlock(loopStmt);
return(loopStmt);
}
/// <summary>
/// Devuelve la cadena a la que corresponde la expresión o null en caso de que esta expresión no tenga ningún alias
/// </summary>
public static string ReplaceStringAliasMembers(Expression ex, IEnumerable<ExprStrRawSql> alias)
{
return alias.Where(x => CompareExpr.ExprEquals(x.Expr, ex)).Select(x => x.Sql).FirstOrDefault();
}
