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How to install PyQt4 on Windows using pip?
I'm using Python 3.4 on Windows. When I run a script, it complains
13 Answers
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Centering a view in its superview using Visual Format Language
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Currently, no, it doesn't look like it is possible to center a view in the superview using only VFL. It is, however, not that difficult to do it using a single VFL string and a single extra constraint (per axis):
VFL: "|-(>=20)-[view]-(...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...so atomic variables are threadsafe (can be accessed from multiple threads without botching of data)
Copy
copy is required when the object is mutable. Use this if you need the value of the object as it is at this moment, and you don't want that value to reflect any changes made by other owners of the...
Why do you need to put #!/bin/bash at the beginning of a script file?
I have made Bash scripts before and they all ran fine without #!/bin/bash at the beginning.
9 Answers
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Virtual Memory Usage from Java under Linux, too much memory used
I have a problem with a Java application running under Linux.
8 Answers
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PHP & mySQL: Year 2038 Bug: What is it? How to solve it?
...g of using TIMESTAMP to store the date+time, but I read that there is a limitation of year 2038 on it. Instead of asking my question in bulk, I preferred to break it up into small parts so that it is easy for novice users to understand as well. So my question(s):
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What is the usefulness of `enable_shared_from_this`?
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It enables you to get a valid shared_ptr instance to this, when all you have is this. Without it, you would have no way of getting a shared_ptr to this, unless you already had one as a member. This example from the boost docu...
Best way to store JSON in an HTML attribute?
...d be any size (i.e. huge).
I've not seen any documentation on browser limits to attribute sizes.
If you do run into them, then store the data in a <script>. Define an object and map element ids to property names in that object.
What if the JSON contains special characters? (e.g. {test: ...
What is the difference between String.slice and String.substring?
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slice() works like substring() with a few different behaviors.
Syntax: string.slice(start, stop);
Syntax: string.substring(start, stop);
What they have in common:
If start equals stop: returns an empty string
If stop is omitted: extracts characters to ...
isset() and empty() - what to use
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It depends what you are looking for, if you are just looking to see if it is empty just use empty as it checks whether it is set as well, if you want to know whether something is set or not use isset.
Empty checks if the var...