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Nullable types and the ternary operator: why is `? 10 : null` forbidden? [duplicate]
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The compiler first tries to evaluate the right-hand expression:
GetBoolValue() ? 10 : null
The 10 is an int literal (not int?) and null is, well, null. There's no implicit conversion between those two hence the error message.
If you change the right-hand expression to ...
How do I make an http request using cookies on Android?
I'd like to make an http request to a remote server while properly handling cookies (eg. storing cookies sent by the server, and sending those cookies when I make subsequent requests). It'd be nice to preserve any and all cookies, but really the only one I care about is the session cookie.
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How to find all occurrences of a substring?
Python has string.find() and string.rfind() to get the index of a substring in a string.
20 Answers
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Negative weights using Dijkstra's Algorithm
I am trying to understand why Dijkstra's algorithm will not work with negative weights. Reading an example on Shortest Paths , I am trying to figure out the following scenario:
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No module named _sqlite3
...sqlite-devel (or libsqlite3-dev on some Debian-based systems)
Re-configure and re-compiled Python with ./configure --enable-loadable-sqlite-extensions && make && sudo make install
Note
The sudo make install part will set that python version to be the system-wide standard, which ...
How to make a edittext box in a dialog
... am trying to make a edittext box in a dialog box for entering a password.
and when I am doing I am not able to do. I am a beginner in it.
Please help me in this.
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How do I add multiple arguments to my custom template filter in a django template?
I looked into django's docs and book but only found example using a single argument... is it even possible?
9 Answers
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Add a property to a JavaScript object using a variable as the name?
I'm pulling items out of the DOM with jQuery and want to set a property on an object using the id of the DOM element.
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Why aren't pointers initialized with NULL by default?
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We all realize that pointer (and other POD types) should be initialized.
The question then becomes 'who should initialize them'.
Well there are basically two methods:
The compiler initializes them.
The developer initializes them.
Let us assume tha...
What are copy elision and return value optimization?
...to a copy or move constructor is elided, that constructor must still exist and must be accessible. This ensures that copy elision does not allow copying objects which are not normally copyable, e.g. because they have a private or deleted copy/move constructor.
C++17: As of C++17, Copy Elision is gua...