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When do you use the “this” keyword? [closed]
...declare extension methods
To pass parameters between constructors
To internally reassign value type (struct) value.
To invoke an extension method on the current instance
To cast itself to another type
To chain constructors defined in the same class
You can avoid the first usage by not having membe...
Received fatal alert: handshake_failure through SSLHandshakeException
... server's certificate is probably not trusted by the client. This would usually result in a more verbose error, but it is quite possible. Usually the fix is to import the server's CA certificate into the client's trust store.
The cerificate is issued for a different domain. Again, this would have re...
Abusing the algebra of algebraic data types - why does this work?
...
Disclaimer: A lot of this doesn't really work quite right when you account for ⊥, so I'm going to blatantly disregard that for the sake of simplicity.
A few initial points:
Note that "union" is probably not the best term for A+B here--that's specifically ...
What is the best way to create constants in Objective-C
...he file in the Reddit-Prefix.pch file to make the constants available to all the files. Is it a good way of doing things? Also, I've done my research and found several methods to create constants, but I don't know which one to use:
...
Python Infinity - Any caveats?
...involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**2
4294967296.0
>>> _**2
1.84467440737...
How to step through Python code to help debug issues?
...
Yes! There's a Python debugger called pdb just for doing that!
You can launch a Python program through pdb by using pdb myscript.py or python -m pdb myscript.py.
There are a few commands you can then issue, which are documented on the pdb page.
Some usef...
What is the difference between task and thread?
...
Jörg W MittagJörg W Mittag
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How can I pretty-print JSON in a shell script?
...ou can use
curl http://my_url/ | python -m json.tool
For convenience in all of these cases you can make an alias:
alias prettyjson='python -m json.tool'
For even more convenience with a bit more typing to get it ready:
prettyjson_s() {
echo "$1" | python -m json.tool
}
prettyjson_f() {...
Symfony 2 EntityManager injection in service
...to inject doctrine EntityManager, but I don't see that __construct() is called on my service, and injection doesn't work.
...
What do linkers do?
...converts the source file into object byte code. This byte code (sometimes called object code) is mnemonic instructions that only your computer architecture understands. Traditionally, these files have an .OBJ extension.
After the object file is created, the linker comes into play. More often than ...