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Executing multi-line statements in the one-line command-line?
...ith Python 3.x as well, print is called as a function: in 3.x, only print('foo') works, whereas 2.x also accepts print 'foo'.
- For a cross-platform perspective that includes Windows, see kxr's helpful answer.
In bash, ksh, or zsh:
Use an ANSI C-quoted string ($'...'), which allows using \n to rep...
MySQL indexes - what are the best practices?
... to the first "%". In other words, if you're SELECTing WHERE column LIKE 'foo%bar%', the database will use the index to find all the rows where column starts with "foo", and then need to scan that intermediate rowset to find the subset that contains "bar". SELECT ... WHERE column LIKE '%bar%' can'...
How to revert a Git Submodule pointer to the commit stored in the containing repository?
...f46a45a4a0d337 sm2
$ cd sm2
$ git log --oneline --decorate
5b8d48f (HEAD, foo1) foo1.1
f68bed6 (origin/master, origin/HEAD, master) Initial commit.
$ git checkout master
Switched to branch 'master'
$ cd ..
$ git status
# On branch master
nothing to commit (working directory clean)
The "superproje...
What's the use of Jade or Handlebars when writing AngularJs apps
... -->
<body ng-controller="MyController">
<input ng-model="foo" value="bar">
<!-- Button tag with ng-click directive, and string expression 'buttonText' wrapped in "{{ }}" markup -->
<button ng-click="changeFoo()">{{buttonText}}</button>
<script src="...
What are the differences between .gitignore and .gitkeep?
...ht be upset. Using !.gitignore prevents you from shooting yourself in your foot. I prefer it, having burned myself in the past.
– sjas
May 13 '14 at 14:44
...
When should I use the new keyword in C++?
...ed on the heap has to be manually deleted by you.
Here's an example:
void foo() {
bar b;
bar* b2 = new bar();
}
This function creates three values worth considering:
On line 1, it declares a variable b of type bar on the stack (automatic duration).
On line 2, it declares a bar pointer b2 on...
“Large data” work flows using pandas
...as_multiple([groups_1,groups_2,.....], where =['field_1>0', 'field_1000=foo'], selector = group_1)
About data_columns, you don't actually need to define ANY data_columns; they allow you to sub-select rows based on the column. E.g. something like:
store.select(group, where = ['field_1000=foo', ...
How to use a class from one C# project with another C# project
... {
static void Main(string[] args)
{
ClassB foo = new ClassB();
Console.WriteLine(foo.textB);
Console.ReadLine();
}
}
}
That SHOULD do the trick
Hope this helps
EDIT::: whoops forgot the method call to actually change the string...
Which, if any, C++ compilers do tail-recursion optimization?
...cade), even for mutually recursive calls such as:
int bar(int, int);
int foo(int n, int acc) {
return (n == 0) ? acc : bar(n - 1, acc + 2);
}
int bar(int n, int acc) {
return (n == 0) ? acc : foo(n - 1, acc + 1);
}
Letting the compiler do the optimisation is straightforward: Just switch...
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...", "0", null, false or [].
Example:
$o = [];
@$var = ["",0,null,1,2,3,$foo,$o['myIndex']];
array_walk($var, function($v) {
echo (!isset($v) || $v == false) ? 'true ' : 'false';
echo ' ' . (empty($v) ? 'true' : 'false');
echo "\n";
});
Test the above snippet in the 3v4l.org online P...