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Using the Swift if let with logical AND operator &&
We know that we can use an if let statement as a shorthand to check for an optional nil then unwrap.
6 Answers
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What is copy-on-write?
I would like to know what copy-on-write is and what it is used for? The term 'copy-on-write array' is mentioned several times in the Sun JDK tutorials but I didn't understand what it meant.
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Do DOM tree elements with ids become global variables?
...ed elements as properties of the window object. This is doubly bad in that now you have to avoid naming your elements after any member of either the document or the window object you (or any other library code in your project) might want to use.
It also means that these elements are visible as glob...
Spring DAO vs Spring ORM vs Spring JDBC
...to the proper DataAccessException subclass.
As an example, suppose you're now using Hibernate, and your service layer catches HibernateException in order to react to it. If you change to JPA, your DAOs interfaces should not change, and the service layer will still compile with blocks that catches H...
What does pylint's “Too few public methods” message mean
...ough if a class seems like the best choice, use it. pylint doesn't always know what's best.
Do note that namedtuple is immutable and the values assigned on instantiation cannot be modified later.
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Convert Year/Month/Day to Day of Year in Python
...ery simple solution:
from datetime import datetime
day_of_year = datetime.now().timetuple().tm_yday
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How can you represent inheritance in a database?
...problems identified for the single table method:
Mandatory attributes can now be enforced with NOT NULL.
Adding a new subtype requires adding a new table instead of adding columns to an existing one.
There is also no risk that an inappropriate attribute is set for a particular subtype, such as th...
Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
Git has a well-known, or at least sort-of-well-known, empty tree whose SHA1 is:
3 Answers
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JavaScript get clipboard data on paste event (Cross browser)
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The situation has changed since writing this answer: now that Firefox has added support in version 22, all major browsers now support accessing the clipboard data in a paste event. See Nico Burns's answer for an example.
In the past this was not generally possible in a cross-b...
Upgrading Node.js to latest version
So, I have Node.js installed and now when I tried to install Mongoosejs I got an error telling me that I don't have the needed version of Node.js (I have v0.4.11 and v0.4.12 is needed).
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