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Can Python print a function definition?
...pile a regular expression pattern, returning a pattern object."
return _compile(pattern, flags)
This will work in the interactive prompt, but apparently only on objects that are imported (not objects defined within the interactive prompt). And of course it will only work if Python can find th...
Setting environment variables for accessing in PHP when using Apache
I have a Linux environment and I have a PHP Web Application that conditionally runs based on environment variables using getenv in PHP. I need to know how these environment variables need to be set for the application to work correctly. I am not sure how to set this up on Apache.
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App Inventor 2 EV3超声波传感器教程 · App Inventor 2 中文网
...通过蓝牙连接EV3，读取各种传感器。
已有文档：bluetooth_remote.md 介绍了蓝牙通信。本文聚焦EV3超声波传感器。
EV3组件
添加组件
组件面板 → LEGO MINDSTORMS → **Ev3 Ultrasonic Sensor`
支持的...
What is the formal difference in Scala between braces and parentheses, and when should they be used?
...ut this, but I gave up in the end, as the rules are somewhat diffuse. Basically, you’ll have to get the hang of it.
Perhaps it is best to concentrate on where curly braces and parenthesis can be used interchangeably: when passing parameters to method calls. You may replace parenthesis with curly b...
Node: log in a file instead of the console
...
Due to a recent change, you can't call stderr.pipe() anymore - it takes this now: process.__defineGetter__('stderr', function() { return fs.createWriteStream(__dirname + '/error.log', {flags:'a'}) })
– damianb
Feb 23 '13 ...
Python add item to the tuple
... @SIslam Without the comma, it will just be interpreted as brackets usually used to get around the order of precedence: (a+b)*c
– Joseph Young
Feb 25 '16 at 5:54
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Which method performs better: .Any() vs .Count() > 0?
...le<T> sequence.
For just IEnumerable<T>, then Any() will generally be quicker, as it only has to look at one iteration. However, note that the LINQ-to-Objects implementation of Count() does check for ICollection<T> (using .Count as an optimisation) - so if your underlying data-sou...
Access object child properties using a dot notation string [duplicate]
...(r, "b.b2"));
//-> 99
Although there are answers that extend this to "allow" array index access, that's not really necessary as you can just specify numerical indexes using dot notation with this method:
getDescendantProp({ a: [ 1, 2, 3 ] }, 'a.2');
//-> 3
...
os.walk without digging into directories below
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Does this function actually "walk" through the whole structure and then delete the entries below a certain point? Or is something more clever going on? I'm not even sure how to check this with code. --python beginner
– mathtic...
Where do I find the current C or C++ standard documents?
...9:1990 Hardcopy available from SAI Global ($88 + shipping)
You cannot usually get old revisions of a standard (any standard) directly from the standards bodies shortly after a new edition of the standard is released. Thus, standards for C89, C90, C99, C++98, C++03 will be hard to find for purchas...