O''''''''Reilly Network For Information About''''''''s Book part 237 ppt

... h.each_pair {| key, value| } Executes the block once for each key-value pair. Pairs are in unspecified order. h.each_key {| key| } Executes the block once for each key. Keys are in unspecified order. ... {| a, b| } Produces an array using h.to_a and returns it sorted. h.store( key, value) Synonym for h[key]=value. h.to_a Returns an array containing the array equivalent (key, v...

Ngày tải lên: 07/07/2014, 08:20

... technical questions about this book, send email to: bookquestions@oreilly.com For information about books, conferences, Resource Centers, and the O'Reilly Network, see the O'Reilly ... favorite technology book, it means the book is available online through the O'Reilly Network Safari Bookshel f. Safari offers a solution that's better than e-books. It's a...

Ngày tải lên: 07/07/2014, 08:20

... complex for no good reason. .3. Typing One of the most fiercely debated topics in programming languages is the benefit of strong, static typing strategies. Java's strategy opts for ... a type is enforced, or interpreted. In a weakly typed language (like C), variables can be coerced easily, or interpreted as something else. A strongly typed language strictly enforces comp...

Ngày tải lên: 07/07/2014, 08:20

... The type is bound to the object. Therefore, the type of containers can change. An imperfect rule of thumb is that static languages force you to declare variables, but dynamic languages ... different, and convert objects that aren't. The extra syntax provides valuethe compiler has more information to catch bugs earlier. There's a cost, too. Static typing makes you work harder...

Ngày tải lên: 07/07/2014, 08:20

... on information in a variable's type. You can't always get the same contextual information out of a Ruby or Smalltalk IDE. 4 http://www.agiledeveloper.com/articles/GenericsInJavaPartI.pdf, ... ever opt for strong, static typing. There are at least two compelling reasons to do so. Static typing reduces certain types of errors (like misspelled variable names), and provides mo...

Ngày tải lên: 07/07/2014, 08:20

... that I interviewed for this book recognized that static typing limits productivity for application development dramatically, though some said they were willing to pay the cost for certain types ... Static typing enforces typing rules at compile time, when they are least expensive to fix.  Static interfaces make it easier to enforce a protocol across important boundaries. For...

Ngày tải lên: 07/07/2014, 08:20

... same syntactic sugar for hashes as for arrays.  Code blocks make iteration tighter and easier. If you're a big Java collections user who's used a dynamic language before, you probably ... 10) = = = 5 => true You get more convenient syntactic sugar. Now, a for loop turns into this: irb(main):021:0> for c in 'g' 'k' irb(main):022:1> puts...

Ngày tải lên: 07/07/2014, 08:20

... always take lessons learned into account), partially due to a lack of performance tuning on the original stack, but mostly due to the fact that the performance gains with Rails are easy to achieve. ... surprised at the level of performance I was able to achieve. The Rails version of the app was fast, and faster even than the original Java version. That's partially due to a bette...

Ngày tải lên: 07/07/2014, 08:20

... approach often makes it much easier to design and refactor complex web screens. For example, here's the rendering for the shopping cart: html divNamed: 'cart' with: [ html small: ... block, so links don't get out of sync. The framework manages them for you.  Seaside is modal. This is the author's word for a continuation server ap proach. Seaside lets...

Ngày tải lên: 07/07/2014, 08:20

... responsible for making sure that the reference count is always correct and, if the reference counter drops to zero, to delete the pointer. Therefore, you must overload those functions for your ... Often, it makes sense to parameterize these functions, and simply forward to member functions of the managed type to do the work (for example, calling add_ref and release). If the referen...

Ngày tải lên: 07/07/2014, 08:20