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How do I print the type of a variable in Rust?
...f you merely wish to find out the type of a variable and are willing to do it at compile time, you can cause an error and get the compiler to pick it up.
For example, set the variable to a type which doesn't work:
let mut my_number: () = 32.90;
// let () = x; would work too
error[E0308]: mismatc...
How to execute a raw update sql with dynamic binding in rails
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It doesn't look like the Rails API exposes methods to do this generically. You could try accessing the underlying connection and using it's methods, e.g. for MySQL:
st = ActiveRecord::Base.connection.raw_connection.prepare("...
Class vs. static method in JavaScript
...ototypal language, rather than a class-based language1. Foo isn't a class, it's a function, which is an object. You can instantiate an object from that function using the new keyword which will allow you to create something similar to a class in a standard OOP language.
I'd suggest ignoring __proto...
retrieve links from web page using python and BeautifulSoup [closed]
... print(link['href'])
The BeautifulSoup documentation is actually quite good, and covers a number of typical scenarios:
https://www.crummy.com/software/BeautifulSoup/bs4/doc/
Edit: Note that I used the SoupStrainer class because it's a bit more efficient (memory and speed wise), if you know w...
Add native files from NuGet package to project output directory
...o a native win32 dll.
I need to pack both the assembly and the native dll with the assembly added to the project references (no problem at this part) and the native dll should be copied into the project output directory or some other relative directory.
...
Rails params explained?
...s, but Ruby on Rails has a special syntax for making the params be a hash with hashes inside. For example, if the user's browser requested
http://www.example.com/?vote[item_id]=1&vote[user_id]=2
then params[:vote] would be a hash, params[:vote][:item_id] would be "1" and params[:vote][:user_i...
Captured variable in a loop in C#
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actions.Add(() => copy * 2);
++ variable;
}
You can think of it as if the C# compiler creates a "new" local variable every time it hits the variable declaration. In fact it'll create appropriate new closure objects, and it gets complicated (in terms of implementation) if you refer to v...
Do sealed classes really offer performance Benefits?
... that you should mark your classes as sealed to get extra performance benefits.
12 Answers
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Django Model - Case-insensitive Query / Filtering
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I solved it like this:
MyClass.objects.filter(name__iexact=my_parameter)
There is even a way to use it for substring search:
MyClass.objects.filter(name__icontains=my_parameter)
There's a link to the documentation.
...
How do I count the number of occurrences of a char in a String?
...or this is:
int count = StringUtils.countMatches("a.b.c.d", ".");
Why write it yourself when it's already in commons lang?
Spring Framework's oneliner for this is:
int occurance = StringUtils.countOccurrencesOf("a.b.c.d", ".");
...