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What is the right way to check for a null string in Objective-C?
...dOfClass:[NSNull class]] is pointlessly complex since [NSNull null] is documented to be a singleton so you can just check for pointer equality. See Topics for Cocoa: Using Null.
So a good test might be:
if (title == (id)[NSNull null] || title.length == 0 ) title = @"Something";
Note how you can ...
What is the recommended way to delete a large number of items from DynamoDB?
...ser_id) -
Without supplying the range, and have it delete everything for me.
An understandable request indeed; I can imagine advanced operations like these might get added over time by the AWS team (they have a history of starting with a limited feature set first and evaluate extensions based on...
Finding a substring within a list in Python [duplicate]
...t is the reasoning behind s for s in list if sub in s ? what does it even mean
– Toskan
Jul 2 at 1:45
add a comment
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Notepad++ - How can I replace blank lines [duplicate]
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@Griffin: The duplicate link I mention beneath the question goes beyond exactly two blank lines.
– BoltClock♦
Aug 12 '11 at 17:57
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Easy interview question got harder: given numbers 1..100, find the missing number(s) given exactly k
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Here's a summary of Dimitris Andreou's link.
Remember sum of i-th powers, where i=1,2,..,k. This reduces the problem to solving the system of equations
a1 + a2 + ... + ak = b1
a12 + a22 + ... + ak2 = b2
...
a1k + a2k + ... + akk = bk
Using Newton's identities, knowin...
How to tell which version of a gem a rails app is using
... This will only work if the gem as been specified in the environment.rb file. If the developer just required it somewhere, rake gems won't work.
– John Hyland
Oct 26 '09 at 19:36
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How to change font size in Eclipse for Java text editors?
... will override the top-level preferences.
Eclipse v4.2 (Juno) note
Per comment below, this has moved to the Eclipse Preferences menu (no longer named the Window menu).
Eclipse v4.3 (Kepler) note
The Window menu is live again, that is, menu Window → Preferences.
Note Be sure to check out the Chan...
Detailed 500 error message, ASP + IIS 7.5
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I have come to the same problem and fixed the same way as Alex K.
So if "Send Errors To Browser" is not working set also this:
Error Pages -> 500 -> Edit Feature Settings -> "Detailed Errors"
Also note that if the conten...
Inconsistent Accessibility: Parameter type is less accessible than method
...e to the currently logged on user, basically) between two forms. At the moment, I have something along these lines in the login form:
...
Rails: Default sort order for a rails model?
...you can also use scope:
class Book < ActiveRecord::Base
scope :confirmed, :conditions => { :confirmed => true }
scope :published, :conditions => { :published => true }
end
For Rails 2 you need named_scope.
:published scope gives you Book.published instead of
Book.find(:publis...