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How do I check if a variable exists?
...have nested functions, variables in outer scopes. If you want to check for all of them, you're probably best off triggering NameError after all.
– Petr Viktorin
Jun 10 '14 at 20:18
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Can someone explain the dollar sign in Javascript?
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I'm not sure I would call that link a "clear" explanation. Does it really take 6+ paragraphs to explain that $ is simply a valid character when defining function and variable names?
– Slight
Mar 20 '15 at 20:...
Using “like” wildcard in prepared statement
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@Alain: Thank you. Just wondering, does this apply to all RDBMS the world is aware of? Perhaps '%' || ? || '%' as mentioned in 1st comment was better, after all? I don't have the opportunity to experiment right now.
– BalusC
Dec 23 '15 at 2...
How to install PyQt4 on Windows using pip?
...ld than just a pure python code package, which means it can be hard to install it from source.
Make sure you grab the correct Windows wheel file (python version, 32/64 bit), and then use pip to install it - e.g:
C:\path\where\wheel\is\> pip install PyQt4-4.11.4-cp35-none-win_amd64.whl
Should ...
Coding in Other (Spoken) Languages
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If I understood well the question actually is: "does every single coder in the world know enough English to use the exact same reserved words as I do?"
Well.. English is not the subject here but programming language reserved words. I mean, when I started about ...
Merging objects (associative arrays)
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with jquery you can call $.extend
var obj1 = {a: 1, b: 2};
var obj2 = {a: 4, c: 110};
var obj3 = $.extend(obj1, obj2);
obj1 == obj3 == {a: 4, b: 2, c: 110} // Pseudo JS
(assoc. arrays are objects in js)
look here: http://api.jquery.com/jQu...
Making an array of integers in iOS
...rays are such a hassle for anything but trivial, one-off use that it's actually less trouble to wrap any arrays you plan on keeping around as NSArrays of NSNumber.
– Chuck
Jul 27 '10 at 1:58
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Why are dashes preferred for CSS selectors / HTML attributes?
...re separated with underscore and there were no stops.
Also, using hyphens allows you to take advantage of the |= attribute selector, which selects any element containing the text, optionally followed by a dash:
span[class|="em"] { font-style: italic; }
This would make the following HTML elements...
Is it possible to have multiple statements in a python lambda expression?
...Q. Can you put multiple statements in a lambda?
A. No. But you don't actually need to use a lambda. You can put the statements in a def instead. i.e.:
def second_lowest(l):
l.sort()
return l[1]
map(second_lowest, lst)
Q. Can you get the second lowest item from a lambda by sorting the ...
How to convert JSON to XML or XML to JSON?
...t in JSON format. Your answer was probably downvoted because it didn't actually answer the question. The OP wasn't asking if he should do the conversion, but rather if he could do it using tools already at his disposal.
– David Brown
Aug 1 '12 at 3:08
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