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Why do we use arrays instead of other data structures?
...gured the added "features" in programming languages had improved upon this and by that replaced them. I see now that they aren't replaced but rather given new life, so to speak.
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How to display gpg key details without importing it?
I have a copy of the postgresql apt repository gpg key and would like to view the details of the gpg key as it comes in the file. Is this possible without importing it into a key ring?
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What's the simplest way to subtract a month from a date in Python?
...// 12
if not m: m = 12
d = min(date.day, [31,
29 if y%4==0 and (not y%100==0 or y%400 == 0) else 28,
31,30,31,30,31,31,30,31,30,31][m-1])
return date.replace(day=d,month=m, year=y)
>>> for m in range(-12, 12):
print(monthdelta(datetime.now(), m))
2009-...
Encode URL in JavaScript?
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Check out the built-in function encodeURIComponent(str) and encodeURI(str).
In your case, this should work:
var myOtherUrl =
"http://example.com/index.html?url=" + encodeURIComponent(myUrl);
shar...
What does @media screen and (max-width: 1024px) mean in CSS?
... as opposed to e.g. an older mobile phone browser (note that the iPhone, and other smartphone browsers, do identify themselves as being in the screen category), or a screenreader — and that it’s displaying the page on-screen, rather than printing it.
max-width: 1024px — the width of the browse...
What does “while True” mean in Python?
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while True means loop forever. The while statement takes an expression and executes the loop body while the expression evaluates to (boolean) "true". True always evaluates to boolean "true" and thus executes the loop body indefinitely. It's an idiom that you'll just get used to eventually! Most ...
PostgreSQL - fetch the row which has the Max value for a column
...that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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What exactly does Perl's “bless” do?
I understand one uses the "bless" keyword in Perl inside a class's "new" method:
8 Answers
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Should I use string.isEmpty() or “”.equals(string)?
...equals(s) is you don't need the null check (equals will check its argument and return false if it's null), which you seem to not care about. If you're not worried about s being null (or are otherwise checking for it), I would definitely use s.isEmpty(); it shows exactly what you're checking, you ca...
What does the Reflect object do in JavaScript?
... http://people.mozilla.org/~jorendorff/es6-draft.html#sec-reflect-object and it sounds similar to the Proxy object apart from the realm and loader functionality.
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