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Calling closure assigned to object property directly
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As of PHP7, you can do
$obj = new StdClass;
$obj->fn = function($arg) { return "Hello $arg"; };
echo ($obj->fn)('World');
or use Closure::call(), though that doesn't work on a StdClass.
Before PHP7, you'd have to implement the magic ...
“implements Runnable” vs “extends Thread” in Java
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Yes: implements Runnable is the preferred way to do it, IMO. You're not really specialising the thread's behaviour. You're just giving it something to run. That means composition is the philosophically "purer" way to go.
In practical terms, it means you can implement Runn...
How to use ADB to send touch events to device using sendevent command?
...g to send touch events to a device using AndroidDebugBridge, so that I can do some basic automation for UI tests. I have followed the discussion in LINK . I am able to use sendevent to simulate touch on emulators, but unable to do the same on a device.
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How to delete/unset the properties of a javascript object? [duplicate]
...s of a JS object so they'll no longer come up if I loop through the object doing for (var i in myObject) . How can this be done?
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How can I apply a function to every row/column of a matrix in MATLAB?
...g, for example, v + 1 , or you can use the function arrayfun . How can I do it for every row/column of a matrix without using a for loop?
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How to turn IDENTITY_INSERT on and off using SQL Server 2008?
Why am I getting an error doing an insert when IDENTITY_INSERT is set to OFF?
8 Answers
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What does the “|” (single pipe) do in JavaScript?
Why does 0.5 | 0 return zero, but any integer (including negative) returns the input integer? What does the single pipe ("|") do?
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Is there an alternative to bastard injection? (AKA poor man's injection via default constructor)
...the intended default would originate in the same assembly, in which case I don't see any particular danger.
In any case you might also consider a Facade as described in one of my earlier answers: Dependency Inject (DI) "friendly" library
BTW, the terminology used here is based on the pattern langu...
When should I choose Vector in Scala?
...nd more memory-efficient for larger-than-trivial sized sequences. See this documentation of the relative performance of Vector compared to the other collections. There are some downsides to going with Vector. Specifically:
Updates at the head are slower than List (though not by as much as you mig...
Querying DynamoDB by date
...At" field.
For more on DynamoDB secondary indexes see the secondary index documentation
Original Answer:
DynamoDB does not allow indexed lookups on the range key only. The hash key is required such that the service knows which partition to look in to find the data.
You can of course perform a s...