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Why does this Java code compile?
...+ 1 is illegal because b is an illegal forward reference to b. You can actually fix this by writing int b = this.b + 1, which compiles without complaints.
For local variables, int d = d + 1 is illegal because d is not initialized before use. This is not the case for fields, which are always default...
Sorting an IList in C#
...ting problem today. We have a WCF web service that returns an IList. Not really a big deal until I wanted to sort it.
15 An...
Checking if array is multidimensional or not?
...will recursively count the array. This is particularly useful for counting all the elements of a multidimensional array. count() does not detect infinite recursion.
However this method does not detect array(array()).
share...
What is the colon operator in Ruby?
..." # false
:foo.equal? :foo # true
This makes comparing two symbols really fast (since only a pointer comparison is involved, as opposed to comparing all the characters like you would in a string), plus you won't have a zillion copies of the same symbol floating about.
Also, unlike strings, sy...
What's the difference between the various methods to get a Context?
...ion about contexts as well:
In a regular Android application, you
usually have two kinds of Context,
Activity and Application.
Reading the article a little bit further tells about the difference between the two and when you might want to consider using the application Context (Activity.get...
Oracle SQL: Update a table with data from another table
...
This is called a correlated update
UPDATE table1 t1
SET (name, desc) = (SELECT t2.name, t2.desc
FROM table2 t2
WHERE t1.id = t2.id)
WHERE EXISTS (
SELECT 1
FROM table2 t2...
Difference between OperationCanceledException and TaskCanceledException?
..., as there aren't any actual tasks involved (at least as far as the public API is concerned). See BlockingCollection.TryTake for an example.
I would catch the OperationCanceledException just in case the task is cancelled due to an operation which itself just threw OperationCanceledException - you p...
Make a Bash alias that takes a parameter?
...reate a function.
alias does not accept parameters but a function can be called just like an alias. For example:
myfunction() {
#do things with parameters like $1 such as
mv "$1" "$1.bak"
cp "$2" "$1"
}
myfunction old.conf new.conf #calls `myfunction`
By the way, Bash functions def...
Copy data into another table
...the column list for newTable is optional if you are specifying a value for all columns and selecting columns in the same order as newTable's schema):
INSERT INTO newTable (col1, col2, col3)
SELECT column1, column2, column3
FROM oldTable
...
How to display the default iOS 6 share action sheet with available share options?
...he UIActivityViewController stated in the other answer makes this trivial. All you have to do is specify the text/image/URL that you want to share and present the activity view controller modally and iOS will automatically display all applicable sharing services. Examples:
Objective-C
- (void)shar...