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NULL vs nil in Objective-C
...
nil should only be used in place of an id, what we Java and C++ programmers would think of as a pointer to an object. Use NULL for non-object pointers.
Look at the declaration of that method:
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object...
How do you specify that a class property is an integer?
...rimenting with TypeScript, and in the process of creating a class with an "ID" field that should be an integer, I have gotten a little confused.
...
What are best practices for REST nested resources?
As far as I can tell each individual resource should have only one canonical path. So in the following example what would good URL patterns be?
...
Tying in to Django Admin's Model History
...min.models import LogEntry, ADDITION
LogEntry.objects.log_action(
user_id = request.user.pk,
content_type_id = ContentType.objects.get_for_model(object).pk,
object_id = object.pk,
object_repr = force_unicode(object),
action_flag = ADDITION
)
where object...
CHECK constraint in MySQL is not working
... answered Jan 22 '10 at 7:11
David KerinsDavid Kerins
1,41911 gold badge88 silver badges33 bronze badges
...
Numbering rows within groups in a data frame
...l, df$cat, FUN = seq_along)
or:
library(plyr)
ddply(df, .(cat), mutate, id = seq_along(val))
or:
library(dplyr)
df %>% group_by(cat) %>% mutate(id = row_number())
or (the most memory efficient, as it assigns by reference within DT):
library(data.table)
DT <- data.table(df)
DT[, id...
405 method not allowed Web API
...ng 405 method not allowed web api) , and finally I added [Route("api/scan/{id}")] to my controller and was work fine.
hope this post help some one.
// DELETE api/Scan/5
[Route("api/scan/{id}")]
[ResponseType(typeof(Scan))]
public IHttpActionResult DeleteScan(int id)
{
...
Sequelize Unknown column '*.createdAt' in 'field list'
..., which creates the following query:
SELECT `users`.*, `userDetails`.`userId` AS `userDetails.userId`,`userDetails`.`firstName` AS `userDetails.firstName`,`userDetails`.`lastName` AS `userDetails.lastName`, `userDetails`.`birthday` AS `userDetails.birthday`, `userDetails`.`id` AS `userDetails.id`, ...
jQuery UI Dialog with ASP.NET button postback
...true,
show: 'Transfer',
hide: 'Transfer',
width: 320,
autoOpen: false,
minHeight: 10,
minwidth: 10
});
dlg.parent().appendTo(...
What is DOM Event delegation?
...ion will continue up to and
including the Document.
Event bubbling provides the foundation for event delegation in browsers. Now you can bind an event handler to a single parent element, and that handler will get executed whenever the event occurs on any of its child nodes (and any of their chil...