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Type List vs type ArrayList in Java [duplicate]
...ssary. Changing ArrayList to List or another List implementation is difficult.
– kgiannakakis
Dec 3 '14 at 8:23
2
...
TypeError: unhashable type: 'dict'
...gt; some_dict[dict_key] = True
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: unhashable type: 'dict'
To use a dict as a key you need to turn it into something that may be hashed first. If the dict you wish to use as key consists of only immutable v...
CSS “and” and “or”
...
&& works by stringing-together multiple selectors like-so:
<div class="class1 class2"></div>
div.class1.class2
{
/* foo */
}
Another example:
<input type="radio" class="class1" />
input[type="radio"].class1
{
/* foo */
}
|| work...
Lambda Expression and generic method
...e compiler could decude a capure type as it does when you declare e.g. Set<?> and do type-checks with those captured types. Sure, that makes it impossible to give them as type-parameters in the body, but if you'd need that, resorting to method references is a good alternative
...
How do I copy a version of a single file from one git branch to another?
...p:
git checkout otherbranch myfile.txt
General formulas:
git checkout <commit_hash> <relative_path_to_file_or_dir>
git checkout <remote_name>/<branch_name> <file_or_dir>
Some notes (from comments):
Using the commit hash you can pull files from any commit
This wo...
How to concatenate text from multiple rows into a single text string in SQL server?
...hn
1 Sam
2 Alaina
2 Edward
Result I expected was:
SubjectID StudentName
---------- -------------
1 Mary, John, Sam
2 Alaina, Edward
I used the following T-SQL:
SELECT Main.SubjectID,
LEFT(Main.Students,Len(...
Returning a value from thread?
... Wouldn't lock(value) { value = "Hello world"; } be better in handling multiple thread value writing?
– checksum
Feb 23 '15 at 7:43
4
...
How do I check to see if a value is an integer in MySQL?
...work on strings, integers, doubles/floats datatypes.
SELECT (LENGTH(CAST(<data> AS UNSIGNED))) = (LENGTH(<data>)) AS is_int
see demo http://sqlfiddle.com/#!9/ff40cd/44
it will fail if the column has a single character value. if column has
a value 'A' then Cast('A' as UNSIGNED) w...
Navigation Drawer (Google+ vs. YouTube)
...:
compile 'com.mikepenz:materialdrawer:5.9.1'
Maven dependency setup:
<dependency>
<groupId>com.mikepenz</groupId>
<artifactId>materialdrawer</artifactId>
<version>5.9.1</version>
</dependency>
...
How to play a local video with Swift?
...tem()
func didFailPlayToEnd()
}
let videoContext:UnsafeMutablePointer<Void> = nil
class VideoPlayer : NSObject {
private var assetPlayer:AVPlayer?
private var playerItem:AVPlayerItem?
private var urlAsset:AVURLAsset?
private var videoOutput:AVPlayerItemVideoOutput?
...