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);
}
internal override PhpTypeCode Emit(CodeGenerator /*!*/ codeGenerator)
{
ILEmitter il = codeGenerator.IL;
LinqBuilder builder = new LinqBuilder(codeGenerator);
builder.DefineContextType();
builder.EmitNewLinqContext();
codeGenerator.LinqBuilder = builder;
LinqOpChain chain = body.BuildChain();
var typecode = chain.Emit(codeGenerator);
// the result is IEnumerable<object>, let's wrap it and pass out
il.Emit(OpCodes.Call, Methods.ClrObject_WrapRealObject);
builder.BakeContextType();
return(PhpTypeCode.Object);
}
internal LinqOpChain BuildChain()
{
// PATTERN (Rule#1):
// q1 into x1 (q2 into x2 ( ... (qm into xm q)...))
//
// TRANSLATION:
// from x1 in ( q1 ), x2 in ( q2 ), ..., xm in ( qm )
// q
List <Generator> generators = new List <Generator>();
QueryBody query = this;
while (query.into != null)
{
LinqOpChain subquery_chain = query.BuildSingleQueryChain(new List <Generator>());
generators.Add(new Generator(Position.Invalid, subquery_chain, query.into.KeyVar, query.into.ValueVar));
query = query.into.NextQuery;
}
return(query.BuildSingleQueryChain(generators));
}
public SelectMany(DirectVarUse keyVar, DirectVarUse valueVar, LinqOpChain innerChain)
{
this.keyVar = keyVar;
this.valueVar = valueVar;
this.innerChain = innerChain;
}
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;
}
}
}
virtual internal void VisitLinqOpChain(Linq.LinqOpChain x)
{
VisitElement(x.Expression);
}
public SelectMany(DirectVarUse keyVar, DirectVarUse valueVar, LinqOpChain innerChain)
{
this.keyVar = keyVar;
this.valueVar = valueVar;
this.innerChain = innerChain;
}
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;
}
}