1 | #Region "Microsoft.VisualBasic::4adfc7297c815c5a00fbe65dd22b7df5, Microsoft.VisualBasic.Core\Language\Language\Perl\die.vb" |
2 | |
3 | ' Author: |
4 | ' |
5 | ' asuka (amethyst.asuka@gcmodeller.org) |
6 | ' xie (genetics@smrucc.org) |
7 | ' xieguigang (xie.guigang@live.com) |
8 | ' |
9 | ' Copyright (c) 2018 GPL3 Licensed |
10 | ' |
11 | ' |
12 | ' GNU GENERAL PUBLIC LICENSE (GPL3) |
13 | ' |
14 | ' |
15 | ' This program is free software: you can redistribute it and/or modify |
16 | ' it under the terms of the GNU General Public License as published by |
17 | ' the Free Software Foundation, either version 3 of the License, or |
18 | ' (at your option) any later version. |
19 | ' |
20 | ' This program is distributed in the hope that it will be useful, |
21 | ' but WITHOUT ANY WARRANTY; without even the implied warranty of |
22 | ' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
23 | ' GNU General Public License for more details. |
24 | ' |
25 | ' You should have received a copy of the GNU General Public License |
26 | ' along with this program. If not, see <http://www.gnu.org/licenses/>. |
27 | |
28 | |
29 | |
30 | ' /********************************************************************************/ |
31 | |
32 | ' Summaries: |
33 | |
34 | ' Structure ExceptionHandle |
35 | ' |
36 | ' Function: [Default] |
37 | ' Operators: (+2 Overloads) Or |
38 | ' |
39 | ' |
40 | ' /********************************************************************************/ |
41 | |
42 | #End Region |
43 | |
44 | Imports System.Drawing |
45 | Imports Microsoft.VisualBasic.Emit.Delegates |
46 | Imports Microsoft.VisualBasic.Language.Default |
47 | |
48 | Namespace Language.Perl |
49 | |
50 | ''' <summary> |
51 | ''' Syntax supports for perl language like exception handler |
52 | ''' |
53 | ''' ```vbnet |
54 | ''' Dim value = func() or die("message") |
55 | ''' ``` |
56 | ''' </summary> |
57 | Public Structure ExceptionHandle |
58 | |
59 | Dim message$ |
60 | Dim failure As Assert(Of Object) |
61 | |
62 | Shared ReadOnly defaultHandler As New Assert(Of Object)(AddressOf [Default]) |
63 | |
64 | ''' <summary> |
65 | ''' Returns True means test failure |
66 | ''' </summary> |
67 | ''' <param name="obj"></param> |
68 | ''' <returns></returns> |
69 | Public Shared Function [Default](obj As Object) As Boolean |
70 | If obj Is Nothing Then |
71 | Return True |
72 | End If |
73 | |
74 | Select Case obj.GetType |
75 | Case GetType(Boolean) |
76 | Return False = DirectCast(obj, Boolean) |
77 | |
78 | ' 对于字符串而言,判断是否为空的标准则是看字符串是否为空或者空字符串 |
79 | Case GetType(String) |
80 | Return String.IsNullOrEmpty(DirectCast(obj, String)) |
81 | |
82 | Case GetType(Double) |
83 | Return CDbl(obj).IsNaNImaginary |
84 | |
85 | Case GetType(TimeSpan) |
86 | Return DirectCast(obj, TimeSpan) = TimeSpan.Zero |
87 | |
88 | Case GetType(Color) |
89 | Return DirectCast(obj, Color).IsEmpty |
90 | |
91 | Case GetType(Rectangle) |
92 | Return DirectCast(obj, Rectangle).IsEmpty |
93 | |
94 | Case GetType(RectangleF) |
95 | Return DirectCast(obj, RectangleF).IsEmpty |
96 | |
97 | Case GetType(Point) |
98 | Return DirectCast(obj, Point).IsEmpty |
99 | |
100 | Case GetType(PointF) |
101 | Return DirectCast(obj, PointF).IsEmpty |
102 | |
103 | Case Else |
104 | |
105 | With obj.GetType |
106 | If .IsInheritsFrom(GetType(Array)) Then |
107 | Return DirectCast(obj, Array).Length = 0 |
108 | |
109 | ElseIf .ImplementInterface(GetType(IEnumerable)) Then |
110 | Return (From o In DirectCast(obj, IEnumerable).AsQueryable).Count = 0 |
111 | |
112 | ElseIf .ImplementInterface(GetType(IsEmpty)) Then |
113 | Return DirectCast(obj, IsEmpty).IsEmpty |
114 | |
115 | Else |
116 | ' False表示没有错误 |
117 | Return False |
118 | End If |
119 | End With |
120 | End Select |
121 | End Function |
122 | |
123 | ''' <summary> |
124 | ''' Perl like exception handler syntax for testing the result is failure or not? |
125 | ''' </summary> |
126 | ''' <param name="result"></param> |
127 | ''' <param name="h"></param> |
128 | ''' <returns></returns> |
129 | Public Shared Operator Or(result As Object, h As ExceptionHandle) As Object |
130 | If h.failure(result) Then |
131 | Throw New Exception(h.message) |
132 | Else |
133 | Return result |
134 | End If |
135 | End Operator |
136 | End Structure |
137 | End Namespace |