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Relative paths in Python
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os.path.dirname(__file__) can give an empty string, use os.path.dirname(os.path.abspath(__file__)) instead
– Dmitry Trofimov
Mar 10 '15 at 22:03
15
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Building big, immutable objects without using constructors having long parameter lists
...method on a case class. Here's some example code:
case class Person(name: String, age: Int, children: List[Person] = List()) {
def addChild(p: Person) = copy(children = p :: this.children)
}
val parent = Person(name = "Bob", age = 55)
.addChild(Person("Lisa", 23))
.addChild(Person("Peter", 1...
What's the advantage of a Java enum versus a class with public static final fields?
...n way without using instanceof, potentially confusing if sequences, or non-string/int switching values. The canonical example is a state machine.
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How to delete an SMS from the inbox in Android programmatically?
...j;
getContentResolver().delete(deleteUri, "address=? and date=?", new String[] {msg.getOriginatingAddress(), String.valueOf(msg.getTimestampMillis())});
I use the originating address and timestamp field to ensure a very high probability of deleting ONLY the message I am interested in. If I w...
How to use ? : if statements with Razor and inline code blocks
... If you need to display the value of a property (including a string) rather than calling ToString() - Which didn't work in my case. You can do this @(condition ? $"{foo.bar}" : "Default")
– Dan Harris
Feb 6 '18 at 16:18
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Scala equivalent of Java java.lang.Class Object
...:
scala> "foo".getClass
res0: java.lang.Class[_ <: java.lang.String] = class java.lang.String
)
Back in 2009:
It would be useful if Scala were to treat the return from getClass() as a java.lang.Class[T] forSome { val T : C } where C is something like the erasure of the static type of...
Should functions return null or an empty object?
...n exception.
Note that if the function was called UserEntity GetUserByName(string name) it would probably not throw but return null. In both cases returning an empty UserEntity would be unhelpful.
For strings, arrays and collections the situation is usually different. I remember some guideline for...
Test or check if sheet exists
...ll the sheets until you find a match.
Function WorksheetExists(shtName As String, Optional wb As Workbook) As Boolean
Dim sht As Worksheet
If wb Is Nothing Then Set wb = ThisWorkbook
On Error Resume Next
Set sht = wb.Sheets(shtName)
On Error GoTo 0
WorksheetExists = Not sht...
What do two question marks together mean in C#?
...null Answer# to Answer (if all Answers are null then the Answer is null):
string Answer = Answer1 ?? Answer2 ?? Answer3 ?? Answer4;
Also it's worth mentioning while the expansion above is conceptually equivalent, the result of each expression is only evaluated once. This is important if for exa...
Get decimal portion of a number with JavaScript
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(2.3 % 1).toFixed(4).substring(2) = "3000" if you need it without the 0.
– Simon_Weaver
Oct 2 '15 at 9:22
15
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