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Rails 3 execute custom sql query without a model
...
Maybe try this:
ActiveRecord::Base.establish_connection(...)
ActiveRecord::Base.connection.execute(...)
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Getting the first character of a string with $str[0]
...ng multibyte encodings (such as UTF-8). If you want to support that, use mb_substr(). Arguably, you should always assume multibyte input these days, so this is the best option, but it will be slightly slower.
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Is there a function to make a copy of a PHP array to another?
... by reference. This means that:
$a = array();
$b = $a;
$b['foo'] = 42;
var_dump($a);
Will yield:
array(0) {
}
Whereas:
$a = new StdClass();
$b = $a;
$b->foo = 42;
var_dump($a);
Yields:
object(stdClass)#1 (1) {
["foo"]=>
int(42)
}
You could get confused by intricacies such as Ar...
Only read selected columns
...,Apr,May,Jun from file",
sep = "\t")
3) With the read_*-functions from the readr-package:
library(readr)
dat <- read_table("data.txt",
col_types = cols_only(Year = 'i', Jan = 'i', Feb = 'i', Mar = 'i',
Apr = 'i', May...
Type hinting a collection of a specified type
...ntainers.
In other words, now you can do:
from typing import List
def my_func(l: List[int]):
pass
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Failed to allocate memory: 8
From today, when I tried to run an app in NetBeans on a 2.3.3 Android platform, it shows me that:
20 Answers
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Method overloading in Objective-C?
...sign pattern)
Here's a simple example on how function overloading works:
__attribute__((overloadable)) float area(Circle * this)
{
return M_PI*this.radius*this.radius;
}
__attribute__((overloadable)) float area(Rectangle * this)
{
return this.w*this.h;
}
//...
//In your Obj-C methods you...
Synchronous request in Node.js
...and pass to the next
endpoints =
[{ host: 'www.example.com', path: '/api_1.php' },
{ host: 'www.example.com', path: '/api_2.php' },
{ host: 'www.example.com', path: '/api_3.php' }];
async.mapSeries(endpoints, http.get, function(results){
// Array of results
});
...
C-like structures in Python
...uct(NamedTuple):
foo: str
bar: int
baz: list
qux: User
my_item = MyStruct('foo', 0, ['baz'], User('peter'))
print(my_item) # MyStruct(foo='foo', bar=0, baz=['baz'], qux=User(name='peter'))
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Best way to iterate through a Perl array
...C instead of Perl, and no needless copying of the array elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)
#5 might be similar.
In terms memory usage: They're all the same except for #5.
for (@a) is special-cased to avoid flattening the a...