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Why is there no Tree class in .NET?
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Beware that elements are un-ordered this way
– Sebastian
Aug 2 '16 at 10:15
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How to use java.String.format in Scala?
...icate positioning. By default, the position of the argument is simply the order in which it appears in the string.
Here's an example of the proper way to use this:
String result = String.format("The format method is %s!", "great");
// result now equals "The format method is great!".
You will a...
How to remove last n characters from every element in the R vector
... an example of what I would do. I hope it's what you're looking for.
char_array = c("foo_bar","bar_foo","apple","beer")
a = data.frame("data"=char_array,"data2"=1:4)
a$data = substr(a$data,1,nchar(a$data)-3)
a should now contain:
data data2
1 foo_ 1
2 bar_ 2
3 ap 3
4 b 4
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How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
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I think you're looking for dispatch_after(). It requires your block to accept no parameters, but you can just let the block capture those variables from your local scope instead.
int parameter1 = 12;
float parameter2 = 144.1;
// Delay execution of my block ...
Duplicating a MySQL table, indices, and data
...oldtable;
To copy just structure and data use this one:
CREATE TABLE tbl_new AS SELECT * FROM tbl_old;
I've asked this before:
Copy a MySQL table including indexes
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Cross field validation with Hibernate Validator (JSR 303)
...ation.Documented;
import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
import static java.lang.annotation.ElementType.TYPE;
import java.lang.annotation.Retention;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
import java.lang.annotation.Target;
/**
* Validation annotation ...
How can I autoformat/indent C code in vim?
...below, etc. All the options are controlled by command line parameters.
In order to use it in vim, just set the formatprg option to it, and then use the gq command. So, for example, I have in my .vimrc:
autocmd BufNewFile,BufRead *.cpp set formatprg=astyle\ -T4pb
so that whenever I open a .cpp fi...
Does Javascript pass by reference? [duplicate]
...y value:
function replace(ref) {
ref = {}; // this code does _not_ affect the object passed
}
function update(ref) {
ref.key = 'newvalue'; // this code _does_ affect the _contents_ of the object
}
var a = { key: 'value' };
replace(a); // a still has its original value - it's un...
python assert with and without parenthesis
...a convenient way to insert debugging assertions into a program:
assert_stmt ::= "assert" expression ["," expression]
The simple form, assert expression, is equivalent to
if __debug__:
if not expression: raise AssertionError
The extended form, assert expression1, expression2, is equi...
How do I convert a Vector of bytes (u8) to a string
...string slice (assuming a UTF-8 encoding):
use std::str;
//
// pub fn from_utf8(v: &[u8]) -> Result<&str, Utf8Error>
//
// Assuming buf: &[u8]
//
fn main() {
let buf = &[0x41u8, 0x41u8, 0x42u8];
let s = match str::from_utf8(buf) {
Ok(v) => v,
E...