aermicioi.aedi.storage.alias

1 /**
2 
3 License:
4 	Boost Software License - Version 1.0 - August 17th, 2003
5 
6     Permission is hereby granted, free of charge, to any person or organization
7     obtaining a copy of the software and accompanying documentation covered by
8     this license (the "Software") to use, reproduce, display, distribute,
9     execute, and transmit the Software, and to prepare derivative works of the
10     Software, and to permit third-parties to whom the Software is furnished to
11     do so, all subject to the following:
12 
13     The copyright notices in the Software and this entire statement, including
14     the above license grant, this restriction and the following disclaimer,
15     must be included in all copies of the Software, in whole or in part, and
16     all derivative works of the Software, unless such copies or derivative
17     works are solely in the form of machine-executable object code generated by
18     a source language processor.
19 
20     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21     IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22     FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
23     SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
24     FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
25     ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26     DEALINGS IN THE SOFTWARE.
27 
28 Authors:
29 	Alexandru Ermicioi
30 **/
31 module aermicioi.aedi.storage.alias_aware;
32 
33 /**
34 Interface for objects that are able to alias an identity and resolve an alias to original identity.
35 **/
36 @safe interface AliasAware(Type) {
37 
38     public {
39 
40         /**
41         Alias a key to an alias_.
42 
43         Params:
44         	identity = the originial identity which is to be aliased.
45         	alias_ = the alias of identity.
46 
47 		Returns:
48 			this
49         **/
50         AliasAware link(Type identity, Type alias_);
51 
52         /**
53         Removes alias.
54 
55         Params:
56         	alias_ = alias to remove.
57 
58         Returns:
59             this
60 
61         **/
62         AliasAware unlink(Type alias_);
63 
64         /**
65         Resolve an alias to original identity, if possible.
66 
67         Params:
68         	alias_ = alias of original identity
69 
70         Returns:
71         	Type the last identity in alias chain.
72 
73         **/
74         const(Type) resolve(in Type alias_) const;
75     }
76 }
77 
78 /**
79 Mix in alias aware interface implementation that delegates
80 the logic to decorated container.
81 **/
82 @safe mixin template AliasAwareMixin(T : AliasAware!W, W) {
83     /**
84     Alias a identity to an alias_.
85 
86     Params:
87         identity = the originial identity which is to be aliased.
88         alias_ = the alias of identity.
89 
90     Returns:
91         this
92     **/
93     AliasAware!W link(W identity, W alias_)
94     in (decorator !is null, "Cannot alias/link one identity to another when decorated aliaser doesn't have decorated object set.")
95     {
96         decorated.link(identity, alias_);
97 
98         return this;
99     }
100 
101     /**
102     Removes alias.
103 
104     Params:
105         alias_ = alias to remove.
106 
107     Returns:
108         this
109 
110     **/
111     AliasAware!W unlink(W alias_)
112     in (decorator !is null, "Cannot dealias/unlink one identity to another when decorated aliaser doesn't have decorated object set.")
113     {
114         decorated.unlink(alias_);
115 
116         return this;
117     }
118 
119     /**
120     Resolve an alias to original identity, if possible.
121 
122     Params:
123         alias_ = alias of original identity
124 
125     Returns:
126         Type the last identity in alias chain.
127 
128     **/
129     const(W) resolve(in W alias_) const
130     in (decorator !is null, "Cannot resolve alias to real identity when decorated aliaser doesn't have decorated object set.")
131     {
132         return decorated_.resolve(alias_);
133     }
134 }
135 
136 /**
137 ditto
138 **/
139 @safe mixin template AliasAwareMixin(T) {
140 
141 }