| CH wrote...
|
|    One simple case - I can state a simple rule, such as 'Only individuals
|    over a certain age may have an SSN'**. That rule needs to be enforced
|    or supported in user interfaces, in business logic layers, and in
|    database layers... But I've yet to see a development environment where the rule
|    can be stated once and never need another line of code written to make it happen.
|
|    Why not? It was a simple enough rule to state... Yet even such
|    a simple rule will require the insertion of snippets of code in a dozen
|    places in an implementation.
|
|    That's the kind of thing I mean... examples are legion, and taken
|    individually there's nothing technically impossible about improving
|    things, but we seem ''unable'' to effectively do it.
|
| AW wrote...
|
|    Here's a way to do it without 'inserting snippets of code'
|
|    Note that these rules work right away in the generic IBL author-user interface.
|    Point a browser to www.reengineeringllc.com, click on 'Internet Business Logic',
|    click GO, than choose the example called OfAgeForSSN1 .
|
|    You can also add a custom UI by extending www.reengineeringllc.com/iblClient1.java .
|
|    Note also that adding a few link rules will make this work over SQL too.
|    (See www.reengineeringllc.com/demo_agents/Oil-IndustrySupplyChain1MySql1.agent
|      for examples of link rules.)
|
|   ** But note that newborns can actually get SSNs now -- See http://www.ssa.gov/pubs/10023.html



some-person is listed in the database
some-age is a possible age
a person must be at least some-number years old to have a social security number
that-age is greater than or equal that-number
some-SSN is an available social security number
add : that-person aged that-age has social security number that-SSN
--------------------------------------------------------------------------------------------------------------
choose person/age/SSN from the menus, then add : that-person aged that-age has social security number that-SSN


some-person aged some-age has social security number some-SSN
del : that-person aged that-age has social security number that-SSN
-----------------------------------------------------------------------------------
delete from the database : that-person aged that-age has social security number that-SSN


this-SSN is an available social security number
===============================================
111-22-3333
222-33-4444


this-person is listed in the database
=====================================
Fred Bloggs
Jim Greene


a person must be at least this-number years old to have a social security number
================================================================================
                           10


this-number is a possible age
==============================
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125



this-person aged this-age has social security number this-SSN 
==============================================================


| This file is an application written in the language Executable English.
| You can view, run and change it by pointing a browser
| to www.reengineeringllc.com and selecting OfAgeForSSN1.