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hasNext in Python iterators?
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@Giorgio, there is no way to know whether another element exists without executing the code that generates it (you don't know whether the generator will execute yield or not). It is, of course, not difficult to write an adaptor that stores the result of n...
How to get my IP address programmatically on iOS/macOS?
...ay 16, 2014 (bug pointed out by lhunath, see comments). Loopback addresses now returned, but its easy for you to uncomment the test to exclude them yourself.
EDIT2: (by some unknown person): Improved further March 13, 2015: In case the user uses a VPN (regardless over WiFi or Cellular), the previou...
How can I tell if a DOM element is visible in the current viewport?
...eed to support version of Internet Explorer before 7.
Original solution (now outdated):
This will check if the element is entirely visible in the current viewport:
function elementInViewport(el) {
var top = el.offsetTop;
var left = el.offsetLeft;
var width = el.offsetWidth;
var height = ...
How many constructor arguments is too many?
...
I know this as the "Named Parameter Idiom": parashift.com/c++-faq-lite/ctors.html#faq-10.18. Related: There is also the "Named Constructor Idiom": parashift.com/c++-faq-lite/ctors.html#faq-10.8
– Frank
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How to copy a row and insert in same table with a autoincrement field in MySQL?
...ou go Stored Procedure you don't go back - you're married to that database now and just adds to the costs whenever you want to change.
– Yzmir Ramirez
Feb 13 '12 at 2:41
11
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How does collections.defaultdict work?
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How do we know what is the default value for each type? 0 for int() and [] for list() are intuitive, but there can also be more complex or self-defined types.
– Sean
Mar 11 at 10:40
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input type=“submit” Vs button tag are they interchangeable?
...lity to adopt to the new spec once it is officialized. HTML5, as of right now, has been official for over one year now, and has been shown in many cases to boost SEO.
&ast; With the exception of <button type="button"> which by default has no specified behaviour.
In summary, I highly di...
What is the point of Lookup?
...ictionary, which doesn't care that two keys correspond to the same value.
Now you want a way of looking up who a given phone number belongs to. You build a Lookup, adding all the KeyValuePairs from your Dictionary, but backwards, with the value as the key and the key as the value. You can now query...
What is the purpose of the “role” attribute in HTML?
...pdate 7 years later (2020): As at least one commenter pointed out, this is now very useful for custom elements, and some spec work is underway to define the default accessibility role of a web component. Even if/once that API is standardized, there may be need to override the default role of a compo...
Pass props to parent component in React.js
...ole app much harder to reason about.
Edit: ES6 examples
As many people now use ES6, here are the same examples for ES6 syntax
The child can be very simple:
const Child = ({
onClick,
text
}) => (
<button onClick={onClick}>
{text}
</button>
)
The parent can be eithe...