public OrderBy(DirectVarUse keyVar, DirectVarUse valueVar, Expression expression,
Ordering ordering, LinqOp next, bool isThenBy)
{
this.keyVar = keyVar;
this.valueVar = valueVar;
this.expression = expression;
this.ordering = ordering;
this.next = next;
this.isThenBy = isThenBy;
}
private static LinqOp BuildOrderingOps(DirectVarUse keyVar, DirectVarUse valueVar,
List <OrderingClause> /*!*/ clauses, LinqOp lastOp)
{
// PATTERNs:
// from x in e orderby k1 , k2, ..., kn [select v | group v by g]
//
// TRANSLATIONs:
// ( e ) . OrderBy ( x => k1 ) . ThenBy ( x => k2 ) ... . ThenBy (x => kn) . Select ( x => v )
// ( e ) . OrderBy ( x => k1 ) . ThenBy ( x => k2 ) ... . ThenBy (x => kn) . GroupBy ( x => g, x => v )
Debug.Assert(clauses != null && clauses.Count > 0);
for (int i = clauses.Count - 1; i >= 0; i--)
{
lastOp = new LinqOp.OrderBy(keyVar, valueVar, clauses[i].Expression, clauses[i].Ordering, lastOp, i != 0);
}
return(lastOp);
}
private static LinqOpChain BuildSelectManyChain(List <Generator> /*!*/ generators,
GroupByClause gbClause, Expression /*!*/ v, LinqOp lastOp)
{
// PATTERNs (Rules #6, #7):
// from x1 in e1 from x2 in e3 ... from xk in ek [select v | group v by g]
//
// TRANSLATIONs:
// ( e1 ) . SelectMany ( x1 =>
// ( e2 ) . SelectMany ( x2 =>
// ...
// RESPECTIVELY:
// ( ek ) . Select ( xk => v )
// ( ek ) . GroupBy ( xk => g, xk => v )
// ...
// )
// )
// . [lastOp]
int i = generators.Count - 1;
LinqOp outer_op; // outer-most operator in the current chain
if (gbClause != null)
{
outer_op = new LinqOp.GroupBy(generators[i].KeyVar, generators[i].ValueVar, gbClause.ByExpr, v);
}
else
{
outer_op = new LinqOp.Select(generators[i].KeyVar, generators[i].ValueVar, v);
}
// inner-most:
LinqOpChain inner_chain = new LinqOpChain(generators[i].Expression, outer_op);
while (--i >= 0)
{
inner_chain = new LinqOpChain(
generators[i].Expression,
outer_op = new LinqOp.SelectMany(generators[i].KeyVar, generators[i].ValueVar, inner_chain)
);
}
outer_op.Next = lastOp;
return(inner_chain);
}
private void FromWhereToGenerators(List <Generator> /*!*/ generators)
{
// query is the inner-most query - it will be converted to OpChain //
int i = 0;
for (; ;)
{
// convert from clauses to generators if there are any;
// (the query can start with where-clause if there was an into-clause):
while (i < fromWhere.Count && fromWhere[i].IsFromClause)
{
FromClause f = (FromClause)fromWhere[i];
// each from-clause contains at least one generator:
Debug.Assert(f.Generators.Count > 0);
// adds generators contained in the from clause (Rule #2):
foreach (Generator generator in f.Generators)
{
generators.Add(generator);
}
i++;
}
// no more clauses:
if (i == fromWhere.Count)
{
break;
}
// where-clause follows; at least one generator has been added:
Debug.Assert(fromWhere[i].IsWhereClause && generators.Count > 0);
Generator last_generator = generators[generators.Count - 1];
DirectVarUse x_key = last_generator.KeyVar;
DirectVarUse x_value = last_generator.ValueVar;
LinqOpChain chain = null;
LinqOp last_op = null;
// embeds where-clauses imediately preceded by a from-clause to
// the last generator of the from-clause (Rule #3):
do
{
LinqOp.Where where_op = new LinqOp.Where(x_key, x_value, ((WhereClause)fromWhere[i]).Expression);
if (last_op == null)
{
chain = new LinqOpChain(last_generator.Expression, where_op);
}
else
{
last_op.Next = where_op;
}
last_op = where_op;
i++;
}while (i < fromWhere.Count && fromWhere[i].IsWhereClause);
Debug.Assert(chain != null);
last_generator.Expression = chain;
// no more clauses:
if (i == fromWhere.Count)
{
break;
}
}
}
private LinqOpChain BuildSingleQueryChain(List <Generator> /*!*/ generators)
{
// Applies Rules #2 and #3
FromWhereToGenerators(generators);
if (generators.Count > 1)
{
// multiple from-clauses (Rules #4 to #7) //
Expression v = (select != null) ? select.Expression : groupBy.GroupExpr;
if (orderBy != null)
{
// PATTERNs (Rules #4, #5):
// from x1 in e1 from x2 in e2 ... from xk in ek orderby k1, k2, ..., kn [select v | group v by g]
//
// TRANSLATIONs:
// ( e1 ) . SelectMany ( x1 =>
// ( e2 ) . SelectMany ( x2 =>
// ...
// RESPECTIVELY:
// ( ek ) . Select ( xk => new Tuple(k1, k2, ..., kn, v) )
// ( ek ) . GroupBy ( xk => g, xk => new Tuple(k1, k2, ..., kn, v) )
// ...
// )
// )
// . OrderBy ( tuple => tuple[0] ) . ... . ThenBy ( tuple => tuple[n - 1] ) . Select ( tuple => tuple[n] )
List <OrderingClause> clauses = orderBy.OrderingClauses;
LinqTuple tuple = new LinqTuple(clauses, v);
LinqOp order_by_ops = BuildTupleOrderingOps(clauses);
return(BuildSelectManyChain(generators, groupBy, tuple, order_by_ops));
}
else
{
// PATTERNs (Rules #6, #7):
// from x1 in e1 from x2 in e3 ... from xk in ek [select v | group v by g]
//
// TRANSLATIONs:
// ( e1 ) . SelectMany ( x1 =>
// ( e2 ) . SelectMany ( x2 =>
// ...
// RESPECTIVELY:
// ( ek ) . Select ( xk => v )
// ( ek ) . GroupBy ( xk => g, xk => v )
// ...
// )
// )
return(BuildSelectManyChain(generators, groupBy, v, null));
}
}
else
{
// single from-clause (Rules #8 to #11) //
DirectVarUse x_key = generators[0].KeyVar;
DirectVarUse x_value = generators[0].ValueVar;
LinqOp last_op;
if (select != null)
{
last_op = new LinqOp.Select(x_key, x_value, select.Expression);
}
else
{
last_op = new LinqOp.GroupBy(x_key, x_value, groupBy.GroupExpr, groupBy.ByExpr);
}
if (orderBy != null)
{
// PATTERNs (Rules #10, #11):
// from x in e orderby k1 , k2, ..., kn [select v | group v by g]
//
// TRANSLATIONs:
// ( e ) . OrderBy ( x => k1 ) . ThenBy ( x => k2 ) ... . ThenBy (x => kn) . Select ( x => v )
// ( e ) . OrderBy ( x => k1 ) . ThenBy ( x => k2 ) ... . ThenBy (x => kn) . GroupBy ( x => g, x => v )
return(new LinqOpChain(
generators[0].Expression,
BuildOrderingOps(x_key, x_value, orderBy.OrderingClauses, last_op)
));
}
else
{
// PATTERNs (Rules #8, #9):
// from x in e [select v | group v by g]
//
// TRANSLATIONs:
// ( e ) . Select ( x => v )
// ( e ) . GroupBy ( x => g, x => v )
return(new LinqOpChain(generators[0].Expression, last_op));
}
}
}
public LinqOpChain(Expression /*!*/ expression, LinqOp firstOp)
: base(Position.Invalid)
{
this.expression = expression;
this.firstOp = firstOp;
}
public LinqOpChain(Expression/*!*/ expression, LinqOp firstOp)
: base(Position.Invalid)
{
this.expression = expression;
this.firstOp = firstOp;
}
public OrderBy(DirectVarUse keyVar, DirectVarUse valueVar, Expression expression,
Ordering ordering, LinqOp next, bool isThenBy)
{
this.keyVar = keyVar;
this.valueVar = valueVar;
this.expression = expression;
this.ordering = ordering;
this.next = next;
this.isThenBy = isThenBy;
}
private static LinqOp BuildOrderingOps(DirectVarUse keyVar, DirectVarUse valueVar,
List<OrderingClause>/*!*/ clauses, LinqOp lastOp)
{
// PATTERNs:
// from x in e orderby k1 , k2, ..., kn [select v | group v by g]
//
// TRANSLATIONs:
// ( e ) . OrderBy ( x => k1 ) . ThenBy ( x => k2 ) ... . ThenBy (x => kn) . Select ( x => v )
// ( e ) . OrderBy ( x => k1 ) . ThenBy ( x => k2 ) ... . ThenBy (x => kn) . GroupBy ( x => g, x => v )
Debug.Assert(clauses != null && clauses.Count > 0);
for (int i = clauses.Count - 1; i >= 0; i--)
lastOp = new LinqOp.OrderBy(keyVar, valueVar, clauses[i].Expression, clauses[i].Ordering, lastOp, i != 0);
return lastOp;
}
private static LinqOpChain BuildSelectManyChain(List<Generator>/*!*/ generators,
GroupByClause gbClause, Expression/*!*/ v, LinqOp lastOp)
{
// PATTERNs (Rules #6, #7):
// from x1 in e1 from x2 in e3 ... from xk in ek [select v | group v by g]
//
// TRANSLATIONs:
// ( e1 ) . SelectMany ( x1 =>
// ( e2 ) . SelectMany ( x2 =>
// ...
// RESPECTIVELY:
// ( ek ) . Select ( xk => v )
// ( ek ) . GroupBy ( xk => g, xk => v )
// ...
// )
// )
// . [lastOp]
int i = generators.Count - 1;
LinqOp outer_op; // outer-most operator in the current chain
if (gbClause != null)
outer_op = new LinqOp.GroupBy(generators[i].KeyVar, generators[i].ValueVar, gbClause.ByExpr, v);
else
outer_op = new LinqOp.Select(generators[i].KeyVar, generators[i].ValueVar, v);
// inner-most:
LinqOpChain inner_chain = new LinqOpChain(generators[i].Expression, outer_op);
while (--i >= 0)
{
inner_chain = new LinqOpChain(
generators[i].Expression,
outer_op = new LinqOp.SelectMany(generators[i].KeyVar, generators[i].ValueVar, inner_chain)
);
}
outer_op.Next = lastOp;
return inner_chain;
}
