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Is there a difference between “==” and “is”?
...0 is 10**3
False
>>> 1000 == 10**3
True
The same holds true for string literals:
>>> "a" is "a"
True
>>> "aa" is "a" * 2
True
>>> x = "a"
>>> "aa" is x * 2
False
>>> "aa" is intern(x*2)
True
Please see this question as well.
...
Is there a Python equivalent of the C# null-coalescing operator?
...
The number 0, None, and empty containers (including strings) are considered false, in addition to the constant False. Most everything else is considered true. I would say that the main danger here would be that you would get a true but non-string value, but that won't be an is...
Include headers when using SELECT INTO OUTFILE?
... and combine files into one CSV file:
CSVHEAD=`/usr/bin/mysql $CONNECTION_STRING -e "$QUERY limit 1;"|head -n1|xargs|sed -e "s/ /'\;'/g"`
echo "\'$CSVHEAD\'" > $TMP/head.txt
/usr/bin/mysql $CONNECTION_STRING -e "$QUERY into outfile '${TMP}/data.txt' fields terminated by ';' optionally enclosed b...
Add and Remove Views in Android Dynamically?
...ew button and the delete button. In my code, I wrote a void inflateEditRow(String) helper function for all the logic.
Other tricks
Set android:animateLayoutChanges="true" in xml to enable animation
Use custom transparent background with pressed selector to make the buttons visually the same as th...
How to find where a method is defined at runtime?
...ou're on Ruby 1.9+, you can use source_location
require 'csv'
p CSV.new('string').method(:flock)
# => #<Method: CSV#flock>
CSV.new('string').method(:flock).source_location
# => ["/path/to/ruby/1.9.2-p290/lib/ruby/1.9.1/forwardable.rb", 180]
Note that this won't work on everything, l...
Can I change a private readonly field in C# using reflection?
...System;
using System.Reflection;
public class Test
{
private readonly string foo = "Foo";
public static void Main()
{
Test test = new Test();
FieldInfo field = typeof(Test).GetField
("foo", BindingFlags.Instance | BindingFlags.NonPublic);
field.SetVa...
Possibility of duplicate Mongo ObjectId's being generated in two different collections?
...eness on a single collection if you use other types for the key, such as a string in your example.
– mstearn
Jan 13 '11 at 6:18
...
How to put a delay on AngularJS instant search?
...es beyond angular itself.
You need set a timeout and compare your current string with the past version, if both are the same then it performs the search.
$scope.$watch('searchStr', function (tmpStr)
{
if (!tmpStr || tmpStr.length == 0)
return 0;
$timeout(function() {
// if searchStr ...
Portable way to get file size (in bytes) in shell?
...ith single fork and single exec, but it uses a temporary file for the here-string. It can be made portable by replacing the here-string with POSX-compliant here-document. BTW note the exec in the subshell. Without that, Bash performs one fork for the subshell and another one for the command running ...
What is the reason why “synchronized” is not allowed in Java 8 interface methods?
... am " + this.getClass() + " . parentFinished. now" + nowStr());
}
private String nowStr() {
return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date());
}
}
public class SonSync1 extends ParentSync {
public void sonStart() {
System.out.println("I am " + this.getClass() + ". sonS...