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dplyr: “Error in n(): function should not be called directly”
...ction" specification, like example below:
delay <- dplyr::summarise(by_tailnum,
count = n(),
dist = mean(distance, na.rm = TRUE),
delay = mean(arr_delay, na.rm = TRUE))
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improv...
Is it good style to explicitly return in Ruby?
...d
Was this meant to be a function that returned a value, or not? It's really hard to say what the developer meant, as it both assigns the instance variable, AND returns the value assigned as well.
Suppose much later, another programmer (perhaps not that familiar with how Ruby does returns based ...
Disable a Button
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I also get an error if I change (_ sender: ) to UIButton . The error reads: Value of type '(UIButton) -> ()' has no member 'isEnabled'
– user9470831
Feb 5 '19 at 4:25
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What is the real overhead of try/catch in C#?
... to make here:
Firstly, there is little or NO performance penalty in actually having try-catch blocks in your code. This should not be a consideration when trying to avoid having them in your application. The performance hit only comes into play when an exception is thrown.
When an exception is th...
Difference between a “coroutine” and a “thread”?
...the baton among each other more fluidly).
Threads are (at least conceptually) a form of concurrent processing: multiple threads may be executing at any given time. (Traditionally, on single-CPU, single-core machines, that concurrency was simulated with some help from the OS -- nowadays, since so...
Load view from an external xib file in storyboard
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Isn't it that loadNibNamed calls init(coder:)? I have a crash trying to adapt your approach.
– Fishman
Nov 14 '16 at 9:15
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How to change Vagrant 'default' machine name?
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I found the multiple options confusing, so I decided to test all of them to see exactly what they do.
I'm using VirtualBox 4.2.16-r86992 and Vagrant 1.3.3.
I created a directory called nametest and ran
vagrant init precise64 http://files.vagrantup.com/precise64.box
to generate a...
Entity Framework: There is already an open DataReader associated with this Command
I am using Entity Framework and occasionally i will get this error.
17 Answers
17
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What is the difference between C, C99, ANSI C and GNU C?
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Everything before standardization is generally called "K&R C", after the famous book, with Dennis Ritchie, the inventor of the C language, as one of the authors. This was "the C language" from 1972-1989.
The first C standard was released 1989 nationally in USA, ...
What are the downsides to using Dependency Injection? [closed]
...
A couple of points:
DI increases complexity, usually by increasing the number of classes since responsibilities are separated more, which is not always beneficial
Your code will be (somewhat) coupled to the dependency injection framework you use (or more generally how you ...