internal SelectOpcode(OpcodeID id, NodeSelectCriteria criteria, OpcodeFlags flags) : base(id)
{
this.criteria = criteria;
base.flags |= flags | OpcodeFlags.Select;
if (criteria.IsCompressable && ((base.flags & OpcodeFlags.InitialSelect) == OpcodeFlags.None))
{
base.flags |= OpcodeFlags.CompressableSelect;
}
}
internal SelectOpcode(OpcodeID id, NodeSelectCriteria criteria, OpcodeFlags flags) : base(id)
{
this.criteria = criteria;
base.flags |= flags | OpcodeFlags.Select;
if (criteria.IsCompressable && ((base.flags & OpcodeFlags.InitialSelect) == OpcodeFlags.None))
{
base.flags |= OpcodeFlags.CompressableSelect;
}
}
internal SelectOpcode(OpcodeID id, NodeSelectCriteria criteria, OpcodeFlags flags)
: base(id)
{
this.criteria = criteria;
this.flags |= (flags | OpcodeFlags.Select);
if (criteria.IsCompressable && (0 == (this.flags & OpcodeFlags.InitialSelect)))
{
this.flags |= OpcodeFlags.CompressableSelect;
}
}
XPathStepExpr ParseStep()
{
QueryAxisType axis = this.ParseAxisSpecifier();
NodeSelectCriteria selectDesc = null;
bool abbreviatedStep = false;
if (QueryAxisType.None != axis)
{
// Valid axis specifier - must be followed by a nodeTest
selectDesc = this.ParseNodeTest(axis);
}
else
{
// No axis specifier. This could be an abbreviated step - shortcuts for 'self' or 'parent'
if (null != this.NextToken(XPathTokenID.Period))
{
selectDesc = new NodeSelectCriteria(QueryAxisType.Self, NodeQName.Empty, QueryNodeType.All);
abbreviatedStep = true;
}
else if (null != this.NextToken(XPathTokenID.DblPeriod))
{
// A shortcut for parent
selectDesc = new NodeSelectCriteria(QueryAxisType.Parent, NodeQName.Empty, QueryNodeType.Ancestor);
abbreviatedStep = true;
}
else
{
// No axis specifier provided. Assume child
if (null == (selectDesc = this.ParseNodeTest(QueryAxisType.Child)))
{
// No nodeTest either.. clearly not a Step
return(null);
}
}
}
if (null == selectDesc)
{
this.ThrowError(QueryCompileError.InvalidLocationStep);
}
XPathExprList predicates = null;
if (!abbreviatedStep)
{
// Abbreviated steps are not permitted predicates
predicates = this.ParsePredicates();
}
return(new XPathStepExpr(selectDesc, predicates));
}
private XPathStepExpr ParseStep()
{
QueryAxisType axisType = this.ParseAxisSpecifier();
NodeSelectCriteria desc = null;
bool flag = false;
if (axisType != QueryAxisType.None)
{
desc = this.ParseNodeTest(axisType);
}
else if (this.NextToken(XPathTokenID.Period) != null)
{
desc = new NodeSelectCriteria(QueryAxisType.Self, NodeQName.Empty, QueryNodeType.All);
flag = true;
}
else if (this.NextToken(XPathTokenID.DblPeriod) != null)
{
desc = new NodeSelectCriteria(QueryAxisType.Parent, NodeQName.Empty, QueryNodeType.Ancestor);
flag = true;
}
else
{
desc = this.ParseNodeTest(QueryAxisType.Child);
if (desc == null)
{
return(null);
}
}
if (desc == null)
{
this.ThrowError(QueryCompileError.InvalidLocationStep);
}
XPathExprList predicates = null;
if (!flag)
{
predicates = this.ParsePredicates();
}
return(new XPathStepExpr(desc, predicates));
}
// Is it possible to select nodes matching the given criteria from nodes of the given type
internal static bool IsSelectPossible(QueryNodeType nodeType, NodeSelectCriteria desc)
{
if (0 != (nodeType & QueryNodeType.Attribute))
{
switch (desc.Axis.Type)
{
default:
return(false);
// Navigation is possible from attributes on these axes
case QueryAxisType.Self:
case QueryAxisType.Ancestor:
case QueryAxisType.AncestorOrSelf:
case QueryAxisType.Parent:
return(true);
}
}
else if (0 != (nodeType & QueryNodeType.Root))
{
if (AxisDirection.Reverse == desc.Axis.Direction)
{
return(false);
}
switch (desc.Axis.Type)
{
default:
return(true);
// Navigation is possible from attributes on these axes
case QueryAxisType.Attribute:
case QueryAxisType.Namespace:
return(false);
}
}
return(true);
}
internal SelectOpcode(NodeSelectCriteria criteria)
: this(OpcodeID.Select, criteria)
{
}
internal XPathStepExpr(NodeSelectCriteria desc, XPathExprList predicates) : base(XPathExprType.PathStep, ValueDataType.Sequence, predicates)
{
this.selectDesc = desc;
}
internal XPathStepExpr(NodeSelectCriteria desc) : this(desc, null)
{
}
XPathStepExpr ParseStep()
{
QueryAxisType axis = this.ParseAxisSpecifier();
NodeSelectCriteria selectDesc = null;
bool abbreviatedStep = false;
if (QueryAxisType.None != axis)
{
// Valid axis specifier - must be followed by a nodeTest
selectDesc = this.ParseNodeTest(axis);
}
else
{
// No axis specifier. This could be an abbreviated step - shortcuts for 'self' or 'parent'
if (null != this.NextToken(XPathTokenID.Period))
{
selectDesc = new NodeSelectCriteria(QueryAxisType.Self, NodeQName.Empty, QueryNodeType.All);
abbreviatedStep = true;
}
else if (null != this.NextToken(XPathTokenID.DblPeriod))
{
// A shortcut for parent
selectDesc = new NodeSelectCriteria(QueryAxisType.Parent, NodeQName.Empty, QueryNodeType.Ancestor);
abbreviatedStep = true;
}
else
{
// No axis specifier provided. Assume child
if (null == (selectDesc = this.ParseNodeTest(QueryAxisType.Child)))
{
// No nodeTest either.. clearly not a Step
return null;
}
}
}
if (null == selectDesc)
{
this.ThrowError(QueryCompileError.InvalidLocationStep);
}
XPathExprList predicates = null;
if (!abbreviatedStep)
{
// Abbreviated steps are not permitted predicates
predicates = this.ParsePredicates();
}
return new XPathStepExpr(selectDesc, predicates);
}
internal SelectOpcode(NodeSelectCriteria criteria) : this(OpcodeID.Select, criteria)
{
}
public bool Equals(NodeSelectCriteria criteria)
{
return (this.axis.Type == criteria.axis.Type && this.type == criteria.type && this.qname.Equals(criteria.qname));
}
internal SelectOpcode(OpcodeID id, NodeSelectCriteria criteria) : this(id, criteria, OpcodeFlags.None)
{
}
internal SelectOpcode(OpcodeID id, NodeSelectCriteria criteria, OpcodeFlags flags)
: base(id)
{
this.criteria = criteria;
this.flags |= (flags | OpcodeFlags.Select);
if (criteria.IsCompressable && (0 == (this.flags & OpcodeFlags.InitialSelect)))
{
this.flags |= OpcodeFlags.CompressableSelect;
}
}
internal InitialSelectOpcode(NodeSelectCriteria criteria)
: base(OpcodeID.InitialSelect, criteria, OpcodeFlags.InitialSelect)
{
}
private XPathStepExpr ParseStep()
{
QueryAxisType axisType = this.ParseAxisSpecifier();
NodeSelectCriteria desc = null;
bool flag = false;
if (axisType != QueryAxisType.None)
{
desc = this.ParseNodeTest(axisType);
}
else if (this.NextToken(XPathTokenID.Period) != null)
{
desc = new NodeSelectCriteria(QueryAxisType.Self, NodeQName.Empty, QueryNodeType.All);
flag = true;
}
else if (this.NextToken(XPathTokenID.DblPeriod) != null)
{
desc = new NodeSelectCriteria(QueryAxisType.Parent, NodeQName.Empty, QueryNodeType.Ancestor);
flag = true;
}
else
{
desc = this.ParseNodeTest(QueryAxisType.Child);
if (desc == null)
{
return null;
}
}
if (desc == null)
{
this.ThrowError(QueryCompileError.InvalidLocationStep);
}
XPathExprList predicates = null;
if (!flag)
{
predicates = this.ParsePredicates();
}
return new XPathStepExpr(desc, predicates);
}
internal SelectOpcode(OpcodeID id, NodeSelectCriteria criteria)
: this(id, criteria, OpcodeFlags.None)
{
}
// Is it possible to select nodes matching the given criteria from nodes of the given type
internal static bool IsSelectPossible(QueryNodeType nodeType, NodeSelectCriteria desc)
{
if (0 != (nodeType & QueryNodeType.Attribute))
{
switch(desc.Axis.Type)
{
default:
return false;
// Navigation is possible from attributes on these axes
case QueryAxisType.Self:
case QueryAxisType.Ancestor:
case QueryAxisType.AncestorOrSelf:
case QueryAxisType.Parent:
return true;
}
}
else if (0 != (nodeType & QueryNodeType.Root))
{
if (AxisDirection.Reverse == desc.Axis.Direction)
{
return false;
}
switch(desc.Axis.Type)
{
default:
return true;
// Navigation is possible from attributes on these axes
case QueryAxisType.Attribute:
case QueryAxisType.Namespace:
return false;
}
}
return true;
}
internal XPathStepExpr(NodeSelectCriteria desc, XPathExprList predicates) : base(XPathExprType.PathStep, ValueDataType.Sequence, predicates)
{
this.selectDesc = desc;
}
public bool Equals(NodeSelectCriteria criteria)
{
return(this.axis.Type == criteria.axis.Type && this.type == criteria.type && this.qname.Equals(criteria.qname));
}
internal InitialSelectOpcode(NodeSelectCriteria criteria)
: base(OpcodeID.InitialSelect, criteria, OpcodeFlags.InitialSelect)
{
}
internal XPathStepExpr(NodeSelectCriteria desc) : this(desc, null)
{
}