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What does an exclamation mark mean in the Swift language?
...pple have chosen to declare the types as implicitly unwrapped, making the calling code more convenient, but less safe.
Perhaps Apple might comb through their frameworks in the future, removing the uncertainty of implicitly unwrapped ("probably never nil") parameters and replacing them with optional...
Build vs new in Rails 3
...ng a new Client object from the clients collection, and so it can automatically set the firm_id to some_firm.id, whereas the docs are calling Client.new which has no knowledge of any Firm's id at all, so it needs the firm_id passed to it.
The only difference between some_firm.clients.new and some_f...
Best way to check if a Data Table has a null value in it
...
I usually create an "Extensions" folder in some common library or in my DAL. Create a file called "DataTableExtensions.cs" and add that method. Next you would just add "using Name.Space.Extensions" to your cs files and have access...
What's “tools:context” in Android layout files?
...
That attribute is basically the persistence for the "Associated Activity" selection above the layout. At runtime, a layout is always associated with an activity. It can of course be associated with more than one, but at least one. In the tool, we ...
Rails: create on has_one association
...
First of all, here is how to do what you want:
@user = current_user
@shop = Shop.create(params[:shop])
@user.shop = @shop
Now here's why your version did not work:
You probably thought that this might work because if User had a ha...
How to write an async method with out parameter?
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@orad I especially like this: private async Task<(bool success, Job job, string message)> TryGetJobAsync(...)
– J. Andrew Laughlin
Oct 26 '18 at 15:26
...
How to change the decimal separator of DecimalFormat from comma to dot/point?
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Side note: NumberFormat.getNumberInstance() can run unusually slowly on some Android 7 devices. An alternative is String.format() which runs quickly. See stackoverflow.com/questions/2379221/java-currency-number-format
– Mr-IDE
Oct 16 '17 at 5:...
C++ unordered_map using a custom class type as the key
...rrides operator(), or as a specialization of std::equal, or – easiest of all – by overloading operator==() for your key type (as you did already).
The difficulty with the hash function is that if your key type consists of several members, you will usually have the hash function calculate hash ...
Close and Dispose - which to call?
...and Dispose in the case of SqlConnectionObject is:
An application can call Close more
than one time. No exception is
generated.
If you called Dispose method
SqlConnection object state will be
reset. If you try to call any
method on disposed SqlConnection
object, you will receive...
Calculating how many minutes there are between two times
...s', this will return only the minutes of timespan [0~59], to return sum of all minutes from this interval, just use 'span.TotalMinutes'.
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