public AST <Node> Substitute(
ASTQueries.NodePredAtom filter,
Func <IEnumerable <ChildInfo>, NodeKind> subKind,
Func <IEnumerable <ChildInfo>, Node> sub,
CancellationToken cancel = default(CancellationToken))
{
var query = new ASTQueries.NodePred[]
{
ASTQueries.NodePredFactory.Instance.Star,
ASTQueries.NodePredFactory.Instance.MkPredicate(NodeKind.Id) & filter
};
if (Root.NodeKind == NodeKind.Id)
{
if (Root.Eval(query[1], ChildContextKind.AnyChildContext, 0, 0))
{
var rootPath = new ChildInfo[] { new ChildInfo(Root, ChildContextKind.AnyChildContext, -1, -1) };
var kind = subKind(rootPath);
var m = sub(rootPath);
return(m.NodeKind != kind ? this : Factory.Instance.ToAST(m));
}
else
{
return(this);
}
}
AST <Node> crntAst = Factory.Instance.ToAST(Root);
this.FindAll(
query,
(pt, x) =>
{
var list = (LinkedList <ChildInfo>)pt;
var prev = list.Last.Previous;
var rkind = subKind(pt);
if (!ASTQueries.ASTSchema.Instance.CanReplace(
prev.Value.Node,
list.Last.Value.Node,
list.Last.Value.Context,
rkind))
{
return;
}
var rep = sub(pt);
if (rep.NodeKind != rkind)
{
return;
}
var newAST = crntAst == this ? this : Factory.Instance.FromAbsPositions(crntAst.Root, pt);
var crnt = ((LinkedList <ChildInfo>)newAST.Path).Last;
var subPath = new LinkedList <ChildInfo>();
Node n = null, p = null;
int pos = -1;
while (crnt != null)
{
n = pos == -1 ? rep : crnt.Value.Node.ShallowClone(p, pos);
pos = crnt.Value.AbsolutePos;
p = n;
subPath.AddFirst(new ChildInfo(n, crnt.Value.Context, pos, crnt.Value.RelativePos));
crnt = crnt.Previous;
}
crntAst = Factory.Instance.ToAST(n);
},
cancel);
crntAst.GetHashCode();
return(crntAst);
}