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Do declared properties require a corresponding instance variable?
...e Modern Objective-C Runtime (that's either iOS 3.x or greater, or 64-bit Snow Leopard or greater) then you do not need to define ivars for your properties in cases like this.
When you @synthesize the property, the ivar will in effect be synthesized also for you. This gets around the "fragile-ivar"...
Run an Application in GDB Until an Exception Occurs
...mes catch is not the best way to debug exception handling: if you need to know exactly where an exception is raised, it is better to stop before the exception handler is called, since that way you can see the stack before any unwinding takes place. If you set a breakpoint in an exception handler ins...
Why can't an anonymous method be assigned to var?
...<T> type that takes a ref anything.
var x2 = y=>123;
We don't know the type of the formal parameter, though we do know the return. (Or do we? Is the return int? long? short? byte?)
var x3 = (int y)=>null;
We don't know the return type, but it can't be void. The return type could be...
Reading binary file and looping over each byte
...
# Do stuff with byte.
byte = f.read(1)
python 3.8
From now on thanks to := operator the above code can be written in a shorter way.
with open("myfile", "rb") as f:
while (byte := f.read(1)):
# Do stuff with byte.
...
How to use auto-layout to move other views when a view is hidden?
...ample) set the view's width to 0, you'll run into two problems. First, you now have double spacing between the superview and the visible view: |-(space)-[hidden(0)]-(space)-[visible] is effectively |-(2*space)-[visible]. Second, that view might start throwing constraint violations depending on its o...
Custom HTTP Authorization Header
...er) explains why introducing a custom header adds the additional burden of now having to manually set the Cache-Control correctly.
– Jon-Eric
Apr 15 '13 at 17:00
...
Everyauth vs Passport.js?
...
Ironically, but passport has much more issues now: github.com/jaredhanson/passport/issues (273 vs. 148 for everyauth).
– Anton Bessonov
Jul 29 '18 at 19:43
...
Performance of Arrays vs. Lists
...sy to measure...
In a small number of tight-loop processing code where I know the length is fixed I use arrays for that extra tiny bit of micro-optimisation; arrays can be marginally faster if you use the indexer / for form - but IIRC believe it depends on the type of data in the array. But unless ...
How do I prompt for Yes/No/Cancel input in a Linux shell script?
...is:
set -- $(locale LC_MESSAGES)
yesptrn="$1"; noptrn="$2"; yesword="$3"; noword="$4"
while true; do
read -p "Install (${yesword} / ${noword})? " yn
case $yn in
${yesptrn##^} ) make install; break;;
${noptrn##^} ) exit;;
* ) echo "Answer ${yesword} / ${noword}.";;
...
Understanding the Gemfile.lock file
...ck in the application together with the Gemfile and Gemfile.lock snapshot. Now, your repository has a record of the exact versions of all of the gems that you used the last time you know for sure that the application worked...
This is important: the Gemfile.lock makes your application a single packa...