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How do I check if a type is a subtype OR the type of an object?
...bclass of an array of int, but they are assignment compatible. IEnumerable<Giraffe> isn't a subclass of IEnumerable<Animal>, but they are assignment compatible in v4.
– Eric Lippert
Apr 30 '10 at 6:07
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Error: Jump to case label
...un, though,
// depends on whether rand returned 0 or 1.
std::cout << i;
}
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Rails 3 check if attribute changed
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Check out ActiveModel::Dirty (available on all models by default). The documentation is really good, but it lets you do things such as:
@user.street1_changed? # => true/false
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What is the difference between bindParam and bindValue?
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@Coldblackice If you were executing the query multiple times with different data. With bindValue you'd need to re-bind the data each time. With bindParam you'd just need to update the variable. The main reason for using bindValue would be static data, e.g. literal strings ...
break out of if and foreach
I have a foreach loop and an if statement. If a match is found i need to ultimately break out of the foreach.
4 Answers
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Path.Combine absolute with relative path strings
...ring absolutePath = Path.GetFullPath(baseDirectory + relativePath);
(result: absolutePath="C:\bling.txt")
What doesn't work
string relativePath = "..\\bling.txt";
Uri baseAbsoluteUri = new Uri("C:\\blah\\");
string absolutePath = new Uri(baseAbsoluteUri, relativePath).AbsolutePath;
(result: a...
Is there documentation for the Rails column types?
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Guidelines built from personal experience:
String:
Limited to 255 characters (depending on DBMS)
Use for short text fields (names, emails, etc)
Text:
Unlimited length (depending on DBMS)
Use for comments, blog posts, etc. General ru...
Returning a C string from a function
...rn this way. Be aware that there are other methods (wide-characters, and multi-byte character systems (mbcs)) that are used to cope with international characters. UTF-8 is an example of an mbcs. For the sake of intro, I quietly 'skip over' all of this.
Memory:
This means that a string like "my str...
Limiting floats to two decimal points
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By the way, since Python 3.6 we can use f-strings: f"Result is {result:.2f}"
– Andrey Semakin
Feb 20 '19 at 12:54
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Can I use if (pointer) instead of if (pointer != NULL)?
...td::nullptr_t
can be converted to a prvalue of
type
bool
; the resulting value is
false
.
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