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parseInt vs unary plus, when to use which?
..., here are a few differences I know of:
An empty string "" evaluates to a 0, while parseInt evaluates it to NaN. IMO, a blank string should be a NaN.
+'' === 0; //true
isNaN(parseInt('',10)); //true
The unary + acts more like parseFloat since it also accepts decimals.
parseInt on...
Adding 'serial' to existing column in Postgres
I have a small table (~30 rows) in my Postgres 9.0 database with an integer ID field (the primary key) which currently contains unique sequential integers starting at 1, but which was not created using the 'serial' keyword.
...
How to change the color of an svg element?
...splay: none;
}
.no-svg .my-svg-alternate {
display: block;
width: 100px;
height: 100px;
background-image: url(image.png);
}
<svg width="96px" height="96px" viewBox="0 0 512 512" enable-background="new 0 0 512 512" xml:space="preserve">
<path id="time-3-icon" d="M256,50C142....
How to determine if a point is in a 2D triangle? [closed]
... d2 = sign(pt, v2, v3);
d3 = sign(pt, v3, v1);
has_neg = (d1 < 0) || (d2 < 0) || (d3 < 0);
has_pos = (d1 > 0) || (d2 > 0) || (d3 > 0);
return !(has_neg && has_pos);
}
share
...
Better way to sum a property value in an array
...ay {
sum(key) {
return this.reduce((a, b) => a + (b[key] || 0), 0);
}
}
const traveler = new TravellerCollection(...[
{ description: 'Senior', Amount: 50},
{ description: 'Senior', Amount: 50},
{ description: 'Adult', Amount: 75},
{ description: 'Child', Amount...
Does opacity:0 have exactly the same effect as visibility:hidden
... in the taborder
collapse events taborder
opacity: 0 No Yes Yes
visibility: hidden No No No
visibility: collapse Yes* No No
display: none Yes No No
* Yes inside a table element, otherwise No.
...
How to open, read, and write from serial port in C?
...ity)
{
struct termios tty;
if (tcgetattr (fd, &tty) != 0)
{
error_message ("error %d from tcgetattr", errno);
return -1;
}
cfsetospeed (&tty, speed);
cfsetispeed (&tty, speed);
tty.c_cflag = (tty.c_...
SQL - The conversion of a varchar data type to a datetime data type resulted in an out-of-range valu
...n other formats like mm/dd/yyyy (usually works).
Specifying the date as 30/12/2013 resulted in the error for me. However, specifying it as mm/dd/yyyy format worked.
If you need to convert your input the you can try looking into the CONVERT method.
Syntax is
CONVERT(VARCHAR,@your_date_Value,103...
~x + ~y == ~(x + y) is always false?
...
|
edited Jun 20 '12 at 13:47
answered Jun 20 '12 at 2:35
...
Ruby 2.0.0p0 IRB warning: “DL is deprecated, please use Fiddle”
...ns of Ruby, removed all of my gems
(including Rails), and installed Ruby 2.0. In other words, a totally clean re-install. Upon starting IRB, I received this message:
...