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What does string::npos mean in this code?
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It means not found.
It is usually defined like so:
static const size_t npos = -1;
It is better to compare to npos instead of -1 because the code is more legible.
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What exactly is nullptr?
We now have C++11 with many new features. An interesting and confusing one (at least for me) is the new nullptr .
14 Answe...
How can I add an item to a IEnumerable collection?
My question as title above. For example,
15 Answers
15
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Anyone else find naming classes and methods one of the most difficult parts in programming? [closed]
...uest help documentation from a vendor through a web service. I try to name it DocumentRetriever , VendorDocRequester , DocGetter , but they just don't sound right. I ended up browsing through dictionary.com for half an hour trying to come up with an adequate word.
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How to generate Class Diagram (UML) on Android Studio (IntelliJ Idea)
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I found a free plugin that can generate class diagrams with android studio.
It's called SimpleUML.
Update Android Studio 2.2+:
To install the plugin, follow steps in this answer: https://stackoverflow.com/a/36823007/1245894
Older version of Android Studio
On Mac: go to Android S...
“is” operator behaves unexpectedly with integers
...ere's what I found in the Python 2 documentation, "Plain Integer Objects" (It's the same for Python 3):
The current implementation keeps an
array of integer objects for all
integers between -5 and 256, when you
create an int in that range you
actually just get back a reference to
the e...
pip installing in global site-packages instead of virtualenv
...ackage in a virtualenv causes the package to be installed in the global site-packages folder instead of the one in the virtualenv folder. Here's how I set up Python3 and virtualenv on OS X Mavericks (10.9.1):
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Command line to remove an environment variable from the OS level configuration
...e variable from the user environment (which is the default place setx puts it):
REG delete HKCU\Environment /F /V FOOBAR
If the variable is set in the system environment (e.g. if you originally set it with setx /M), as an administrator run:
REG delete "HKLM\SYSTEM\CurrentControlSet\Control\Sessi...
When is layoutSubviews called?
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I had a similar question, but wasn't satisfied with the answer (or any I could find on the net), so I tried it in practice and here is what I got:
init does not cause layoutSubviews to
be called (duh)
addSubview: causes
layoutSubviews to be called on the
view being adde...
Why is #!/usr/bin/env bash superior to #!/bin/bash?
I've seen in a number of places, including recommendations on this site ( What is the preferred Bash shebang? ), to use #!/usr/bin/env bash in preference to #!/bin/bash . I've even seen one enterprising individual suggest using #!/bin/bash was wrong and bash functionality would be lost by doing...