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Xcode: Build Failed, but no error messages
...uilding fine for the last three months, but suddenly, when I try to build, it says "Build failed", but does not show any errors on the triangle exclamation mark tab, nor does it give a reason when it pops up build failed.
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Defining an abstract class without any abstract methods
Can I define an abstract class without adding an abstract method?
12 Answers
12
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What is pip's equivalent of `npm install package --save-dev`?
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There isn't an equivalent with pip.
Best way is to pip install package && pip freeze > requirements.txt
You can see all the available options on their documentation page.
If it really bothers you, it wouldn't be too difficult to write a ...
How can I create a keystore?
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To answer the question in the title, you create a keystore with the Java Keytool utility that comes with any standard JDK distribution and can be located at %JAVA_HOME%\bin. On Windows this would usually be C:\Program Files\Java\jre7\bin.
So on Windows, op...
How to remove a key from Hash and get the remaining hash in Ruby/Rails?
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Rails has an except/except! method that returns the hash with those keys removed. If you're already using Rails, there's no sense in creating your own version of this.
class Hash
# Returns a hash that includes everything but the given keys.
# hash = { a: true, b: false, c: n...
Difference between TCP and UDP?
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TCP is a connection oriented stream over an IP network. It guarantees that all sent packets will reach the destination in the correct order. This imply the use of acknowledgement packets sent back to the sender, and automatic retransmission, causing additional delays and a general...
How to create a cron job using Bash automatically without the interactive editor?
Does crontab have an argument for creating cron jobs without using the editor (crontab -e). If so, What would be the code create a cronjob from a Bash script?
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If isset $_POST
I have a form on one page that submits to another page. There, it checks if the input mail is filled. If so then do something and if it is not filled, do something else. I don't understand why it always says that it is set, even if I send an empty form. What is missing or wrong?
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What's the difference between utf8_general_ci and utf8_unicode_ci?
...tation from early MySQL versions which remains only for backward compatibility. The fixed version was given the name utf8mb4.
Note: Newer versions of MySQL have updated Unicode sorting rules, available under names such as utf8mb4_0900_ai_ci for equivalent rules based on Unicode 9.0 - and with no equ...
Why are my basic Heroku apps taking two seconds to load?
I created two very simple Heroku apps to test out the service, but it's often taking several seconds to load the page when I first visit them:
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