diff --git a/CommandLine/CLI/IORedirectFile.vb b/CommandLine/CLI/IORedirectFile.vb
index 556d61b7..5c3177af 100644
--- a/CommandLine/CLI/IORedirectFile.vb
+++ b/CommandLine/CLI/IORedirectFile.vb
@@ -223,7 +223,7 @@ Namespace CommandLine
                 Wait:=True
             )
 #End If
-            Call path.Delete
+            Call path.DeleteFile
 
             Return exitCode
         End Function
diff --git a/ComponentModel/Ranges/RangeModel/DoubleRange.vb b/ComponentModel/Ranges/RangeModel/DoubleRange.vb
index 3efcf721..d8e1c084 100644
--- a/ComponentModel/Ranges/RangeModel/DoubleRange.vb
+++ b/ComponentModel/Ranges/RangeModel/DoubleRange.vb
@@ -1,47 +1,47 @@
 #Region "Microsoft.VisualBasic::5129b125d626e728e29e3e3caeeccf56, Microsoft.VisualBasic.Core\ComponentModel\Ranges\RangeModel\DoubleRange.vb"
 
-    ' Author:
-    ' 
-    '       asuka (amethyst.asuka@gcmodeller.org)
-    '       xie (genetics@smrucc.org)
-    '       xieguigang (xie.guigang@live.com)
-    ' 
-    ' Copyright (c) 2018 GPL3 Licensed
-    ' 
-    ' 
-    ' GNU GENERAL PUBLIC LICENSE (GPL3)
-    ' 
-    ' 
-    ' This program is free software: you can redistribute it and/or modify
-    ' it under the terms of the GNU General Public License as published by
-    ' the Free Software Foundation, either version 3 of the License, or
-    ' (at your option) any later version.
-    ' 
-    ' This program is distributed in the hope that it will be useful,
-    ' but WITHOUT ANY WARRANTY; without even the implied warranty of
-    ' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    ' GNU General Public License for more details.
-    ' 
-    ' You should have received a copy of the GNU General Public License
-    ' along with this program. If not, see <http://www.gnu.org/licenses/>.
+' Author:
+' 
+'       asuka (amethyst.asuka@gcmodeller.org)
+'       xie (genetics@smrucc.org)
+'       xieguigang (xie.guigang@live.com)
+' 
+' Copyright (c) 2018 GPL3 Licensed
+' 
+' 
+' GNU GENERAL PUBLIC LICENSE (GPL3)
+' 
+' 
+' This program is free software: you can redistribute it and/or modify
+' it under the terms of the GNU General Public License as published by
+' the Free Software Foundation, either version 3 of the License, or
+' (at your option) any later version.
+' 
+' This program is distributed in the hope that it will be useful,
+' but WITHOUT ANY WARRANTY; without even the implied warranty of
+' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+' GNU General Public License for more details.
+' 
+' You should have received a copy of the GNU General Public License
+' along with this program. If not, see <http://www.gnu.org/licenses/>.
 
 
 
-    ' /********************************************************************************/
+' /********************************************************************************/
 
-    ' Summaries:
+' Summaries:
 
-    '     Class DoubleRange
-    ' 
-    '         Properties: Length, Max, Min
-    ' 
-    '         Constructor: (+6 Overloads) Sub New
-    '         Function: Enumerate, GetEnumerator, IEnumerable_GetEnumerator, (+3 Overloads) IsInside, (+2 Overloads) IsOverlapping
-    '                   ScaleMapping, (+2 Overloads) ToString, TryParse
-    '         Operators: *, <>, =
-    ' 
-    ' 
-    ' /********************************************************************************/
+'     Class DoubleRange
+' 
+'         Properties: Length, Max, Min
+' 
+'         Constructor: (+6 Overloads) Sub New
+'         Function: Enumerate, GetEnumerator, IEnumerable_GetEnumerator, (+3 Overloads) IsInside, (+2 Overloads) IsOverlapping
+'                   ScaleMapping, (+2 Overloads) ToString, TryParse
+'         Operators: *, <>, =
+' 
+' 
+' /********************************************************************************/
 
 #End Region
 
@@ -55,6 +55,7 @@ Imports System.Runtime.CompilerServices
 Imports System.Xml.Serialization
 Imports Microsoft.VisualBasic.Language
 Imports Microsoft.VisualBasic.Language.Vectorization
+Imports Microsoft.VisualBasic.Linq
 
 Namespace ComponentModel.Ranges.Model
 
@@ -62,7 +63,7 @@ Namespace ComponentModel.Ranges.Model
     ''' Represents a double range with minimum and maximum values
     ''' </summary>
     Public Class DoubleRange : Implements IRanges(Of Double)
-        Implements IEnumerable(Of Double)
+        Implements Enumeration(Of Double)
 
         ''' <summary>
         ''' Minimum value
@@ -284,13 +285,13 @@ Namespace ComponentModel.Ranges.Model
             Return value
         End Function
 
-        Public Overridable Iterator Function GetEnumerator() As IEnumerator(Of Double) Implements IEnumerable(Of Double).GetEnumerator
+        Public Overridable Iterator Function GetEnumerator() As IEnumerator(Of Double) Implements Enumeration(Of Double).GenericEnumerator
             For Each x In Me.Enumerate(100)
                 Yield x
             Next
         End Function
 
-        Private Iterator Function IEnumerable_GetEnumerator() As IEnumerator Implements IEnumerable.GetEnumerator
+        Private Iterator Function IEnumerable_GetEnumerator() As IEnumerator Implements Enumeration(Of Double).GetEnumerator
             Yield GetEnumerator()
         End Function
 
diff --git a/Extensions/IO/Extensions/PathExtensions.vb b/Extensions/IO/Extensions/PathExtensions.vb
index 582a88c2..b4b27daa 100644
--- a/Extensions/IO/Extensions/PathExtensions.vb
+++ b/Extensions/IO/Extensions/PathExtensions.vb
@@ -1,60 +1,58 @@
 #Region "Microsoft.VisualBasic::9594e92f3956920f5661adb6dd2e6ff0, Microsoft.VisualBasic.Core\Extensions\IO\Extensions\PathExtensions.vb"
 
-    ' Author:
-    ' 
-    '       asuka (amethyst.asuka@gcmodeller.org)
-    '       xie (genetics@smrucc.org)
-    '       xieguigang (xie.guigang@live.com)
-    ' 
-    ' Copyright (c) 2018 GPL3 Licensed
-    ' 
-    ' 
-    ' GNU GENERAL PUBLIC LICENSE (GPL3)
-    ' 
-    ' 
-    ' This program is free software: you can redistribute it and/or modify
-    ' it under the terms of the GNU General Public License as published by
-    ' the Free Software Foundation, either version 3 of the License, or
-    ' (at your option) any later version.
-    ' 
-    ' This program is distributed in the hope that it will be useful,
-    ' but WITHOUT ANY WARRANTY; without even the implied warranty of
-    ' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    ' GNU General Public License for more details.
-    ' 
-    ' You should have received a copy of the GNU General Public License
-    ' along with this program. If not, see <http://www.gnu.org/licenses/>.
+' Author:
+' 
+'       asuka (amethyst.asuka@gcmodeller.org)
+'       xie (genetics@smrucc.org)
+'       xieguigang (xie.guigang@live.com)
+' 
+' Copyright (c) 2018 GPL3 Licensed
+' 
+' 
+' GNU GENERAL PUBLIC LICENSE (GPL3)
+' 
+' 
+' This program is free software: you can redistribute it and/or modify
+' it under the terms of the GNU General Public License as published by
+' the Free Software Foundation, either version 3 of the License, or
+' (at your option) any later version.
+' 
+' This program is distributed in the hope that it will be useful,
+' but WITHOUT ANY WARRANTY; without even the implied warranty of
+' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+' GNU General Public License for more details.
+' 
+' You should have received a copy of the GNU General Public License
+' along with this program. If not, see <http://www.gnu.org/licenses/>.
 
 
 
-    ' /********************************************************************************/
+' /********************************************************************************/
 
-    ' Summaries:
+' Summaries:
 
-    ' Module PathExtensions
-    ' 
-    '     Function: BaseName, ChangeSuffix, Delete, DIR, DirectoryExists
-    '               DirectoryName, EnumerateFiles, ExtensionSuffix, FileCopy, (+2 Overloads) FileExists
-    '               FileLength, FileMove, FileName, FileOpened, GetBaseName
-    '               GetDirectoryFullPath, GetFile, GetFullPath, GetMostAppreancePath, ListDirectory
-    '               ListFiles, LoadEntryList, (+3 Overloads) LoadSourceEntryList, Long2Short, (+2 Overloads) NormalizePathString
-    '               ParentDirName, ParentPath, PathCombine, PathIllegal, ReadDirectory
-    '               (+2 Overloads) RelativePath, SafeCopyTo, SourceCopy, SplitPath, TheFile
-    '               ToDIR_URL, ToFileURL, TrimDIR, TrimSuffix, UnixPath
-    ' 
-    '     Sub: MkDIR
-    ' 
-    ' /********************************************************************************/
+' Module PathExtensions
+' 
+'     Function: BaseName, ChangeSuffix, Delete, DIR, DirectoryExists
+'               DirectoryName, EnumerateFiles, ExtensionSuffix, FileCopy, (+2 Overloads) FileExists
+'               FileLength, FileMove, FileName, FileOpened, GetBaseName
+'               GetDirectoryFullPath, GetFile, GetFullPath, GetMostAppreancePath, ListDirectory
+'               ListFiles, LoadEntryList, (+3 Overloads) LoadSourceEntryList, Long2Short, (+2 Overloads) NormalizePathString
+'               ParentDirName, ParentPath, PathCombine, PathIllegal, ReadDirectory
+'               (+2 Overloads) RelativePath, SafeCopyTo, SourceCopy, SplitPath, TheFile
+'               ToDIR_URL, ToFileURL, TrimDIR, TrimSuffix, UnixPath
+' 
+'     Sub: MkDIR
+' 
+' /********************************************************************************/
 
 #End Region
 
-Imports System.Collections.ObjectModel
 Imports System.IO
 Imports System.Math
 Imports System.Reflection
 Imports System.Runtime.CompilerServices
 Imports System.Text
-Imports System.Text.RegularExpressions
 Imports Microsoft.VisualBasic.CommandLine.Reflection
 Imports Microsoft.VisualBasic.ComponentModel.DataSourceModel
 Imports Microsoft.VisualBasic.FileIO
@@ -99,10 +97,10 @@ Public Module PathExtensions
     ''' <summary>
     ''' Execute file delete
     ''' </summary>
-    ''' <param name="path$"></param>
+    ''' <param name="path">The file path or the directory path.</param>
     ''' <param name="throwEx"></param>
     ''' <returns></returns>
-    <Extension> Public Function Delete(path$, Optional throwEx As Boolean = False) As Boolean
+    <Extension> Public Function DeleteFile(path$, Optional throwEx As Boolean = False) As Boolean
         Try
             If path.FileExists Then
                 Call FileIO.FileSystem.DeleteFile(