public IExpr <T> Process <T>(IExpr <T> expr)
{
return((IExpr <T>)expr.Patch(this));
}
public IExpr Process(IExpr expr) => expr.Patch(this);
public static IExpr Map(this IExpr expr, Func<IExpr, IExpr> f)
{
var dic = new Dictionary<IExpr, IExpr>();
_fillDic(expr, f, dic);
return expr.Patch(new Patch(dic));
}