"Features are good. They set Firefox apart from others, and attract users. What bothers users is features that don’t have a mature user interface. The solution should be to fix the interface, not drop the feature."
Event-driven programming is widely used in [[graphical user interfaces] because it has been adopted by most commercial widget toolkits as the model for interaction. The design of those toolkits has been criticized for promoting an over-simplified model of event-action, leading programmers to create error prone, difficult to extend and excessively complex application code:
Such an approach is fertile ground for bugs for at least three reasons:
1. It always leads to convoluted conditional logic.
2. Each branching point requires evaluation of a complex expression.
3. Switching between different modes requires modifying many variables, which all can easily lead to inconsistencies.
Instead of a low level action-reaction, Miro Samek proposes a better approach using finite State Machines to control the interaction logic necessary to define the state changes to incoming events. Hierarchical State Machines have also been proposed as a high-level model for reactive programs. The UML language in particular provides a complete specification to represent state machines.
Some alternate implementations:
http://accu.org/index.php/journals/252
http://www.eventhelix.com/RealtimeMantra/HierarchicalStateMachine.htm
def with_failable_rbinding(first_divisor)Here you have a do-block containing a sequence of divisions composed using the special monadic assignment =xx. Everything executed within the block is handled by the Failable monad, wich is programmed to return a special non-numeric Failure value when a division by 0 is performed:
with_monad Failable do
val1 =xx fdiv(2.0, first_divisor)
val2 =xx fdiv(3.0, 1.0)
val3 =xx fdiv(val1, val2)
val3
end
end
puts fdiv_with_binding(1.0)
=> Success(0.666666666666667)
puts fdiv_with_binding(0.0)
=> Failure(cannot divide by zero)
DataDraw is an ultra-fast persistent database for high performance programs written in C. It's so fast that many programs keep all their data in a DataDraw database, even while being manipulated in inner loops of compute intensive applications. Unlike slow SQL databases, DataDraw databases are compiled, and directly link into your C programs. DataDraw databases are resident in memory, making data manipulation even faster than if they were stored in native C data structures (really). Further, they can automatically support infinite undo/redo, greatly simplifying many applications.
JavaScript is one of the most widely used languages in web development. It's simple, yet very powerful, and the number of ways that it can be used are almost limitless. That's why it's so important to gather advice from those who have gone before you. Here are 10 tips from well-respected web developers within the JavaScript community.
The underlying concept is very simple: spreadsheets are a way to organize text, numbers and formulas into what might be seen as a natively numeric environment: a matrix. So what would happen if we loosed some of the bolts of the numeric-oriented organization, and tried to reuse the same concepts into a more formatting-oriented environment which is naturally collaborative: a wiki.
IT Mill Toolkit comes with a large collection of RIA components, suited for all types of applications. Each component is thoroughly tested in real-world applications to ensure high quality.
I've implemented in Python the undo algorithm found in ``Undoing Actions in Collaborative Work: Framework and Experience'' by Prakash and Knister [cite PK94]. Their approach helps structure the objects that make up a ``document''. Those same objects are well suited for use in an embedded language like Python: with them you can write scripts that can be undone! I've implemented standard file operations as a simple concrete example of using the framework.
