Your code will work fine: the weak reference will not cause a retain cycle as you explicitly instruct ARC not to increase the retainCount of your weak object. For best practice, however, you should create a strong reference of your object using the weak one. This won’t create a retain cycle either as the strong … Read more
For understanding more about magento block types following are some built-in block types which are widely used in layout. core/template: This block renders a template defined by its template attribute. The majority of blocks defined in the layout are of type or subtype of core/template. page/html: This is a subtype of core/template and defines the root block. All other blocks … Read more
What does 64MB block size mean? The block size is the smallest data unit that a file system can store. If you store a file that’s 1k or 60Mb, it’ll take up one block. Once you cross the 64Mb boundary, you need a second block. If yes, what is the advantage of doing that? HDFS … Read more
Some methods take a block, and this pattern frequently appears for a block: {|x| x.foo} and people would like to write that in a more concise way. In order to do that they use a combination of: a symbol, the method Symbol#to_proc, implicit class casting, and & operator. If you put & in front of … Read more
The difference is precedence: # Equivalent to puts( (1..10).map { |i| i*2 } ) > puts (1..10).map { |i| i*2 } 2 4 6 8 10 12 14 16 18 20 => nil # Equivalent to puts( (1..10).map ) { |i| i*2 } > puts (1..10).map do |i| i*2 end #<Enumerator:0x928f24> => nil In the … Read more
Because the language spec says so: http://docs.oracle.com/javase/specs/jls/se7/html/jls-6.html A declaration introduces an entity into a program and includes an identifier (§3.8) that can be used in a name to refer to this entity. A declared entity is one of the following: … A local variable, one of the following: * A local variable declared in a … Read more
I offer up my own explanation from this answer, slightly modified: “Blocks” in Ruby are not the same as the general programming terms “code block” or “block of code”. Pretend for a moment that the following (invalid) Ruby code actually worked: def add10( n ) puts “#{n} + 10 = #{n+10}” end def do_something_with_digits( method … Read more
Try this: version(:full) { process(:resize_to_limit => [960, 960]) } version(:half) { process(:resize_to_limit => [470, 470]) } version(:third) { process(:resize_to_limit => [306, 306]) } version(:fourth) { process(:resize_to_limit => [176, 176]) } You have a precedence problem. The { } block binds tighter than a do…end block and tighter than a method call; the result is that … Read more
Polling like this is definitely the least preferred solution. I assume that you have another thread that will do something to make the condition true. There are several ways to synchronize threads. The easiest one in your case would be a notification via an Object: Main thread: synchronized(syncObject) { try { // Calling wait() will … Read more
You can’t use the completion Block to create a return value for your method. The AFJSONRequestOperation does its work asynchronously. someFunction is going to return while the operation is still working. The success and failure Blocks are how you get resulting values where they need to go. One option here is to pass in the … Read more