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In Objective-C why should I check if self = [super init] is not nil?
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For example:
[[NSData alloc] initWithContentsOfFile:@"this/path/doesn't/exist/"];
[[NSImage alloc] initWithContentsOfFile:@"unsupportedFormat.sjt"];
[NSImage imageNamed:@"AnImageThatIsntInTheImageCache"];
... and so on. (Note: NSData might throw...
Remove columns from DataTable in C#
... which I get a DataTable from that I am being passed back from a function call. It has 15-20 columns, however I only want 10 columns of the data.
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SQLAlchemy ORDER BY DESCENDING?
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This is a potentially brittle workaround where a workaround is not needed.
– BlueBomber
Jun 25 '13 at 14:41
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favicon.png vs favicon.ico - why should I use PNG instead of ICO?
...updates and notes from various others in this thread:
ICOs and PNGs both allow full alpha channel based transparency
ICO allows for backwards compatibility to older browsers (e.g. IE6)
PNG probably has broader tooling support for transparency, but you can find tools to create alpha-channel ICOs as...
Convert LocalDate to LocalDateTime or java.sql.Timestamp
... Watch out when converting LocalDateTime to DateTime as not all LocalDateTimes are valid DateTimes. Source: joda-time.sourceforge.net/faq.html#illegalinstant and just running into this.
– Christophe De Troyer
Aug 10 '15 at 8:53
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Bash if [ false ] ; returns true
...ce "false" is a non-empty string, the test command always succeeds. To actually run the command, drop the [ command.
if false; then
echo "True"
else
echo "False"
fi
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Python pip install fails: invalid command egg_info
I find that recently often when I try to install a Python package using pip , I get the error(s) below.
15 Answers
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Uncaught SyntaxError: Unexpected token with JSON.parse
...n into a Javascript object.
Your code turns the object into a string (by calling .toString()) in order to try to parse it as JSON text.
The default .toString() returns "[object Object]", which is not valid JSON; hence the error.
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How do I drop a MongoDB database from the command line?
...ul in my case. Somehow I had a database named "mean-dev" from an older installation, and entering "mean-dev.dropDatabase()" in the mongo shell resulted in "ReferenceError: mean is not defined". But using the solution in this answer did the trick. +1
– K. P. MacGregor
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What do 'lazy' and 'greedy' mean in the context of regular expressions?
...xr, a great tool that will help you explore Regular Expressions - I use it all the time.
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