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What are best practices for validating email addresses on iOS 2.0
... ; "]", or "\"
Yes, that means +, ', etc are all legit.
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Rails Migration: Remove constraint
I have a table in a Rails application which (in schema.rb) looks like:
2 Answers
2
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How does the Comma Operator work
...he comma operator quite cleverly to implement list initializers for symbol tables. Thus, it makes the following syntax possible and meaningful:
keywords = "and", "or", "not", "xor";
Notice that due to operator precedence, the code is (intentionally!) identical to
(((keywords = "and"), "or"), "no...
“Too many values to unpack” Exception
...nATupleWithThreeValues()
print a
print b
raises
Traceback (most recent call last):
File "c.py", line 3, in ?
a,b = returnATupleWithThreeValues()
ValueError: too many values to unpack
Now, the reason why this happens in your case, I don't know, but maybe this answer will point you in the r...
Chrome, Javascript, window.open in new tab
...pup’) by specifying options in the 3rd parameter
3. If the window.open call was not part of a user-initiated event, it’ll open in a new window.
4. A “user initiated event” does not have to the same function call – but it must originate in the function invoked by a user click
5. If a use...
What is the JavaScript convention for no operation?
... "function" // returns true
It can be invoked as a function and essentially does nothing as shown here:
setTimeout(function() {
console.log('Start: ', Date.now());
Function.prototype();
console.log('End : ', Date.now());
}, 1000);
Although this is a "true noop" since...
What is the use of “assert” in Python?
...t True # nothing happens
>>> assert False
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
Assertions can include an optional message, and you can disable them when running the interpreter.
To print a message if the assertion fails:
ass...
How to delete all Annotations on a MKMapView
Is there a simple way to delete all the annotations on a map without iterating through all the displayed annotations in Objective-c?
...
Why does the MongoDB Java driver use a random number generator in a conditional?
...k && Math.random() <= 0.1)
return res;
The commit that originally introduced this logic had
if (_ok == true) {
_logger.log( Level.WARNING , "Server seen down: " + _addr, e );
} else if (Math.random() < 0.1) {
_logger.log( Level.WARNING , "Server seen down: " + _addr );
}
—a...
What are Flask Blueprints, exactly?
...he string mold in Blueprint("mold", __name__)
– Codevalley
Aug 7 '17 at 6:48
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