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Why is isNaN(null) == false in JS?
...is a value of the numeric data type representing an undefined or unrepresentable value, especially in floating-point calculations.
In most cases we think the answer to "is null numeric?" should be no. However, isNaN(null) == false is semantically correct, because null is not NaN.
Here's the algor...
c# datatable insert column at position 0
does anyone know the best way to insert a column in a datatable at position 0?
3 Answers
...
phpmyadmin logs out after 1440 secs
...in install path (ex. /usr/share/phpMyAdmin/ on my centos7) and find create_tables.sql in one of its subfolders (phpMyAdmin/sql/create_tables.sql in my 4.4.9 version.) and execute whole file contents on your current phpMyAdmin site from your web browser. This will create a database named phpmyadmin w...
Is it possible to use 'else' in a list comprehension? [duplicate]
...t; [a if a else 2 for a in [0,1,0,3]]
[2, 1, 2, 3]
So for your example,
table = ''.join(chr(index) if index in ords_to_keep else replace_with
for index in xrange(15))
share
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imp...
Difference between Activity Context and Application Context
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I found this table super useful for deciding when to use different types of Contexts:
An application CAN start an Activity from here, but it requires that a new task be created. This may fit specific use cases, but can create non-sta...
Difference between jQuery `click`, `bind`, `live`, `delegate`, `trigger` and `on` functions (with an
...ler automatically. This is very common when you have some kind of lists or tables, where you add rows or cells dynamically, but want them all to behave in the same way. Instead of going to all the pain of assigning event handlers anew every time, you can use the .live method:
<a class="myLink"&g...
What does (x ^ 0x1) != 0 mean?
...hex notation
x ^ 0x1 will invert the last bit of x (refer to the XOR truth table in the link above if that's not clear to you).
So, the condition (0 != ( x ^ 0x1 )) will be true if x is greater than 1 or if the last bit of x is 0. Which only leaves x==1 as a value at which the condition will be fa...
Passing Data between View Controllers
...igationController pushViewController:vc animated:NO];
fire block
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:
(NSIndexPath *)indexPath {
NSString *voucher = vouchersArray[indexPath.row];
if (sourceVC.selectVoucherBlock) {
sourceVC.selectVoucherBlock(voucher)...
Unique constraint that allows empty values in MySQL
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@MianAnjum bolded: CREATE TABLE table (key int(11) NOT NULL AUTO_INCREMENT, field tinyint(1) DEFAULT NULL)
– Paul Nowak
Sep 19 '17 at 19:45
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