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javascript set a variable if undefined
...efined. It would therefore not only match undefined but also null, false, 0, NaN, "" (but not "0").
If you want to set to default only if the variable is strictly undefined then the safest way is to write:
var x = (typeof x === 'undefined') ? your_default_value : x;
On newer browsers it's actu...
Why doesn't indexOf work on an array IE8?
...exOf = function(elt /*, from*/)
{
var len = this.length >>> 0;
var from = Number(arguments[1]) || 0;
from = (from < 0)
? Math.ceil(from)
: Math.floor(from);
if (from < 0)
from += len;
for (; from < len; from++)
{
if (from in...
Error 908: Permission Receive SMS - #5 by Taifun - MIT App Inventor Help - MIT App Inventor Community
...imary: #222222;
--secondary: #ffffff;
--tertiary: #0088cc;
--quaternary: #e45735;
--highlight: #ffff4d;
--success: #009900;
}
}
/* then deal with dark scheme */
@media (prefers-color-scheme: dark) {
...
Format a number as 2.5K if a thousand or more, otherwise 900
...its not an even thousands, otherwise if under a thousand, display normal 500, 100, 250 etc, using javascript to format the number?
...
Named colors in matplotlib
..._names)
ncols = 4
nrows = n // ncols
fig, ax = plt.subplots(figsize=(12, 10))
# Get height and width
X, Y = fig.get_dpi() * fig.get_size_inches()
h = Y / (nrows + 1)
w = X / ncols
for i, name in enumerate(sorted_names):
row = i % nrows
col = i // nrows
y = Y - (row * h) - h
xi_li...
C++ auto keyword. Why is it magic?
...r templates on any compiler that even sort of attempted to implement C++98/03. As such, adding support for auto was apparently fairly easy for essentially all the compiler teams--it was added quite quickly, and there seem to have been few bugs related to it either.
When this answer was originally w...
Iterate a list with indexes in Python
...e this [3, 7, 19] and makes it into iterable list of tuples, like so: [(0,3), (1,7), (2,19)] to use it instead of:
6 An...
How would I get a cron job to run every 30 minutes?
I'm looking to add a crontab entry to execute a script every 30 minutes, on the hour and 30 minutes past the hour or something close. I have the following, but it doesn't seem to run on 0.
...
Why a function checking if a string is empty always returns true? [closed]
...if ($strTemp !== '')
since != '' will return true if you pass is numeric 0 and a few other cases due to PHP's automatic type conversion.
You should not use the built-in empty() function for this; see comments and the PHP type comparison tables.
...