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In which situations do we need to write the __autoreleasing ownership qualifier under ARC?
...ents that are passed by reference (id *) and are autoreleased on return.
All of this is very well explained in the ARC transition guide.
In your NSError example, the declaration means __strong, implicitly:
NSError * e = nil;
Will be transformed to:
NSError * __strong error = nil;
When you c...
Draw text in OpenGL ES
I'm currently developing a small OpenGL game for the Android platform and I wonder if there's an easy way to render text on top of the rendered frame (like a HUD with the player´s score etc). The text would need to use a custom font also.
...
How to properly reuse connection to Mongodb across NodeJs application and modules
...lhost:27017";
var _db;
module.exports = {
connectToServer: function( callback ) {
MongoClient.connect( url, { useNewUrlParser: true }, function( err, client ) {
_db = client.db('test_db');
return callback( err );
} );
},
getDb: function() {
return _db;
}
};
To...
How to calculate the SVG Path for an arc (of a circle)
...
This is super! Note that the arcSweep variable is actually controlling the large-arc-flag svg A parameter. In the above code, the value for the sweep-flag parameter is always zero. arcSweep should probably be renamed to something like longArc.
– Steven Gr...
Reference alias (calculated in SELECT) in WHERE clause
...probably consider a computed column (and perhaps persisted) instead, especially if a lot of queries refer to this same expression.
PS your fears seem unfounded. In this simple example at least, SQL Server is smart enough to only perform the calculation once, even though you've referenced it twice. ...
How do you serialize a model instance in Django?
...
You can easily use a list to wrap the required object and that's all what django serializers need to correctly serialize it, eg.:
from django.core import serializers
# assuming obj is a model instance
serialized_obj = serializers.serialize('json', [ obj, ])
...
How to linebreak an svg text within javascript?
...extArea element, with automatic word wrapping, but it's not implemented in all browsers. SVG 2 does not plan on implementing textArea, but it does have auto-wrapped text.
However, given that you already know where your linebreaks should occur, you can break your text into multiple <tspan>s, e...
Makefile, header dependencies
...vided by the gnu preprocessor are a bit confusing. However, the removal of all directories from the build target with -MM is documented and not a bug [gpp]:
By default CPP takes the name of the main input file, deletes any
directory components and any file suffix such as ‘.c’, and appends ...
Get the first item from an iterable that matches a condition
...ment against next (in that answer) is that you must handle an exception; really ?
– Abraham TS
Jan 24 '18 at 23:34
My ...
What does the JSLint error 'body of a for in should be wrapped in an if statement' mean?
...
First of all, never use a for in loop to enumerate over an array. Never. Use good old for(var i = 0; i<arr.length; i++).
The reason behind this is the following: each object in JavaScript has a special field called prototype. Ever...