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find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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Why would you use String.Equals over ==? [duplicate]
I recently was introduced to a large codebase and noticed all string comparisons are done using String.Equals() instead of ==
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Error handling principles for Node.js + Express.js applications?
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Error handling in Node.js is generally of the format A). Most callbacks return an error object as the first argument or null.
Express.js uses middleware and the middleware syntax uses B) and E) (mentioned below).
C) is bad practice if you ask me.
app.get('...
iPhone App Minus App Store?
... member of the developer program. You can then use the adhoc system to install your application onto up to 100 devices. The developer program has the details but it involves adding UUIDs for each of the devices to your application package. UUIDs can be easiest retrieved using Ad Hoc Helper available...
Scala: What is the difference between Traversable and Iterable traits in Scala collections?
...ersables don't.
A Traversable has one abstract method: foreach. When you call foreach, the collection will feed the passed function all the elements it keeps, one after the other.
On the other hand, an Iterable has as abstract method iterator, which returns an Iterator. You can call next on an Ite...
Mediator Vs Observer Object-Oriented Design Patterns
...-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically.
The Mediator pattern:
Define an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each o...
Cleaner way to do a null check in C#? [duplicate]
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Is this really considered cleaner?
– ClassicThunder
Jul 16 '13 at 13:35
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MySQL: Can't create table (errno: 150)
... child table InnoDB engine. Current create.sql script was using InnoDB for all tables, but I had very very old installation where first script used MyISAM.
– Whome
Apr 8 '13 at 9:50
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do you have kcachegrind like profiling tools for mac [closed]
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I ended up using qcachegrind on OSX. It can be installed via brew
brew install qcachegrind
or, to enable graphviz support:
brew install qcachegrind --with-graphviz
What's great about this program is that I successfully loaded a 6.1GB cachegrind file on my MacBook Pro! P...
How to remove the first character of string in PHP?
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Note that lrtim will remove all :::::. Sometimes this is not desired behavior.
– CoR
Nov 20 '13 at 14:02
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