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When to use enumerateObjectsUsingBlock vs. for
...need to modify local variables" - not true; you can declare your locals as __block and they'll be writable in the block.
enumerateObjectsWithOptions:usingBlock: supports either concurrent or reverse enumeration.
with dictionaries, block based enumeration is the only way to retrieve the key and value...
What and where are the stack and heap?
...ion is called. The stack is always reserved in a LIFO (last in first out) order; the most recently reserved block is always the next block to be freed. This makes it really simple to keep track of the stack; freeing a block from the stack is nothing more than adjusting one pointer.
The heap is me...
XPath contains(text(),'some string') doesn't work when used with node with more than one Text subnod
...ng the string-value of the node in the node-set that is first in document order. Hence, it can match only the first text node in your <Comment> element -- namely BLAH BLAH BLAH. Since that doesn't match, you don't get a <Comment> in your results.
You need to change this to
//*[text(...
How to use Elasticsearch with MongoDB?
...abase through the mongo shell and push some dummy data into it.
mongo YOUR_DATABASE_NAME
db.createCollection(YOUR_COLLECTION_NAME)
for (var i = 1; i <= 25; i++) db.YOUR_COLLECTION_NAME.insert( { x : i } )
Now to Convert the standalone MongoDB into a Replica Set.
First Shutdown the process.
m...
Authorize a non-admin developer in Xcode / Mac OS
...
You need to add your OS X user name to the _developer group. See the posts in this thread for more information. The following command should do the trick:
sudo dscl . append /Groups/_developer GroupMembership <username>
...
What is a good regular expression to match a URL? [duplicate]
...t to ensure URL starts with HTTP/HTTPS:
https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_\+.~#?&//=]*)
If you do not require HTTP protocol:
[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_\+.~#?&//=]*)
To try this out see http...
@UniqueConstraint annotation in Java
...
@Entity
@Table(uniqueConstraints={@UniqueConstraint(columnNames = {"id_1" , "id_2"})})
public class class_name {
@Id
@GeneratedValue
public Long id;
@NotNull
public Long id_1;
@NotNull
public Long id_2;
}
Hope it helped.
...
Const before or const after?
...
The order of the keywords in a declaration isn't all that fixed. There are many alternatives to "the one true order". Like this
int long const long unsigned volatile i = 0;
or should it be
volatile unsigned long long int con...
Debugging in Clojure? [closed]
...race) java.io.FileNotFoundException: Could not locate closure/contrib/trace__init.class or closure/contrib/trace.clj on classpath: (NO_SOURCE_FILE:0)
– LarsH
Sep 3 '10 at 20:49
2
...
Can I access constants in settings.py from templates in Django?
..., frequently-used settings constants to the template such as settings.MEDIA_URL and some of the language settings if you use django's built in generic views or pass in a context instance keyword argument in the render_to_response shortcut function. Here's an example of each case:
from django.short...
