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Compare if two variables reference the same object in python
...st only once and reuses them. Special values such as (), None, True, False etc are defined to be singletons too. During execution the runtime also tries to reuse small numbers and strings, but in the end it's a tradeoff between speed and memory and what happends depends on how the Python runtime was...
Measuring text width to be drawn on Canvas ( Android )
...omAsset(getAssets(), "Helvetica.ttf");
paint.setTypeface(typeface);
paint.setColor(Color.BLACK);
paint.setStyle(Paint.Style.FILL);
Rect result = new Rect();
paint.getTextBounds(finalVal, 0, finalVal.length(), result);
Log.i("Text dimensions", "Width: "+result.width()+"-Height: "+result.height());
...
How to create an array containing 1…N
...alues by changing i+1 to expression required (e.g. i*2, -i, 1+i*2, i%2 and etc). If expression can be expressed by some function f then the first form becomes simply
[ ...Array(N).keys() ].map(f)
Examples:
Array.from({length: 5}, (v, k) => k+1);
// [1,2,3,4,5]
Since the array is initialize...
gdb: how to print the current line or find the current line number?
...n pointer regardless of architecture — it will work on i386, x86_64, ARM etc..
– Ruslan
Aug 17 '16 at 9:23
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How can I make a weak protocol reference in 'pure' Swift (without @objc)
...inherit from NSObject! And presumably it's not namespace'd anymore either, etc. In short: \@objc is a bridging feature, not a language one.
– hnh
Jun 7 '14 at 11:46
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How to skip over an element in .map()?
... With all these negative, "empty"-style values (null, undefined, NaN etc) it would be good if we could utilise one inside a map() as an indicator that this object maps to nothing and should be skipped. I often come across arrays I want to map 98% of (eg: String.split() leaving a single, empty...
What is the difference between #import and #include in Objective-C?
...PILED_HEADER_SHARING, GCC_PRECOMPILE_PREFIX_HEADER, and GCC_PREFIX_HEADER, etc.
Also, while not well-documented… You can create module.maps for your own frameworks and include them in the same convenient fashion. You can take a look at my ObjC-Clang-Modules github repo for some examples of how t...
What is the difference between 0.0.0.0, 127.0.0.1 and localhost?
... normally the hostname for the 127.0.0.1 IP address. It's usually set in /etc/hosts (or the Windows equivalent named "hosts" somewhere under %WINDIR%). You can use it just like any other hostname - try "ping localhost" to see how it resolves to 127.0.0.1.
0.0.0.0 has a couple of different meanings...
How do I perform the SQL Join equivalent in MongoDB?
... is small. It is going to bring each book content to your client and then fetch each category, lending and authors one by one. The moment your books are in thousands, this would go really really slow. A better technique probably would be to use aggregation pipeline and output the merged data into a...
In Python, how do I use urllib to see if a website is 404 or 200?
...
The getcode() method (Added in python2.6) returns the HTTP status code that was sent with the response, or None if the URL is no HTTP URL.
>>> a=urllib.urlopen('http://www.google.com/asdfsf')
>>> a.getcode()
404...