Questions tagged [design-patterns]
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14
questions
6
votes
1answer
1k views
Is there a way of objectively measuring the efficiency or quality of software or code design?
I've been thinking about ways of measuring code, and, quite frankly, I can't think of truly objective, semi-universal ways of evaluating the quality or "strength" of code to say, "Yes, this is better ...
4
votes
2answers
224 views
What's the difference between declarative syntax and encapsulation?
I had been first introduced to the idea of declarative syntax when using Angular JS. From what I understand, the idea is that you say, "do this" instead of "in order to do this, do this, this and this"...
3
votes
3answers
529 views
Design patterns for simple text based scripting language?
In my current application I am trying to determine the best way to implement a simple scripting language. This language would allow a user to create a script that controls a machine with various ...
3
votes
2answers
43 views
Is there a formal term for functions that have static state across executions?
Two examples, one in PHP:
function adder($i){
static $a = 0;
$a += $i;
return $a;
}
A similar effect can be achieved with closures in javascript:
...
1
vote
1answer
38 views
design cache system using queuing theory
If we have data from a random population, a 3d histogram of throughput and current cache size of DRAM (intersection of a IOPS & a cache size will have a count). How can one use queuing theory to ...
1
vote
1answer
106 views
What is the difference between a “meta model” and “design patterns”?
Where is the difference between a "meta model" and "design patterns"?
If you take, for example, Fowlers "Identity Field" from his book "Patterns Of Enterprise Application Architecture": Why is this a ...
1
vote
0answers
34 views
Building an architecture without pointers, objects, memory allocation or first class functions [closed]
Many sources for good software architecture will use objects, pointers, memory allocation in their solutions. The PLC programming language 61131-3 Structured Text is really limited in this regard, ...
1
vote
1answer
2k views
Combine abstract factory with decorator pattern [closed]
I'm working on a simple project of software engineering that should combine two patterns.
I choose Abstract Factory and Decorator patterns to modify (dynamically) objects created with the concrete ...
0
votes
1answer
26 views
How does this example violate Liskov substitution principle, which then causes violation of the open-closed principle?
From Agile Principles, Patterns, and Practices in C# by Robert Martin,
Listing 10-1. A violation of LSP causing a violation of OCP
...
0
votes
1answer
38 views
State Machine and State transition Table - Explanation and Creation Of
How do I create a state transition table/array in actual code/pseudo-code?
I haven't experienced the "ah-ha" moment yet with the state machine to coding (and I really want to). I've looked at several ...
0
votes
0answers
15 views
How do I erase the “shadow-world” antipattern?
In this antipattern, you have level-0 constructs of the language, which are then abstracted over by creating level-1 constructions, and these level-1 abstractions are abstracted over by creating level-...
0
votes
0answers
30 views
What are the pros and cons of these two coding patterns/structures? And do they have a formal term?
I have traditionally been doing things like this:
function test() // A
{
if (/* conditions */)
return true;
else
return false;
}
Of late, ...
0
votes
0answers
28 views
Finite state machine for a modified traffic controller
Consider a traffic light controller for an intersection of a main street and a smaller street. Both streets are one-way streets. The intersection has two traffic lights, one for each street. In normal ...
0
votes
0answers
14 views
What is the difference between a composite and a leaf in a composite pattern?
I think the initial is sometimes called a compositor. Essentially from the diagrams of what I have seen so far from the design pattern is that compositors are more complex in its attributes while the ...
