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Python pip install fails: invalid command egg_info
... edited Jun 5 '14 at 10:33
evandrix
5,36333 gold badges2525 silver badges3232 bronze badges
answered Jul 11 '12 at 5:01
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In Objective-C, how do I test the object type?
...
If your object is myObject, and you want to test to see if it is an NSString, the code would be:
[myObject isKindOfClass:[NSString class]]
Likewise, if you wanted to test myObject for a UIImageView:
[myObject isKindOfClass:[UIImageView class]]
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Faster way to develop and test print stylesheets (avoid print preview every time)?
...P (Mac) or Ctrl+Shift+P (Windows, Linux))
2. Start typing Rendering and select Show Rendering.
3. For the Emulate CSS Media dropdown, select print.
UPDATE 29/02/2016
The DevTools docs have moved and the above link provides inaccurate information. The updated docs regarding Media type em...
ExecJS and could not find a JavaScript runtime
I'm trying to use the Mongoid / Devise Rails 3.1 template ( Mongoid and Devise ), and I keep getting an error stating ExecJS cannot find a JavaScript runtime. Fair enough when I didn't have any installed, but I've tried installing Node.js , Mustang and the Ruby Racer , but nothing is work...
SQL order string as number
...u can't do that then cast your column value to an integer explicitly with
select col from yourtable
order by cast(col as unsigned)
or implicitly for instance with a mathematical operation which forces a conversion to number
select col from yourtable
order by col + 0
BTW MySQL converts strings...
Django: How do I add arbitrary html attributes to input fields on a form?
...$list.each(function () {
$(this).addClass('form-control')
});
var $select = $("#django_form select");
$select.each(function () {
$(this).addClass('custom-select w-90')
});
var $list = $("#django_form :input[type='number']");
$list.each(function () {
$(this).addClass('form-con...
MySQL skip first 10 results
Is there a way in MySQL to have the first 10 result from a SELECT query skipped?
I'd like it to work something like LIMIT.
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What is the difference between '>' and a space in CSS selectors?
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A > B will only select B that are direct children to A (that is, there are no other elements inbetween).
A B will select any B that are inside A, even if there are other elements between them.
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How do I check in SQLite whether a table exists?
...sed that FAQ entry.
Anyway, for future reference, the complete query is:
SELECT name FROM sqlite_master WHERE type='table' AND name='{table_name}';
Where {table_name} is the name of the table to check.
Documentation section for reference: Database File Format. 2.6. Storage Of The SQL Database S...
Group by month and year in MySQL
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I prefer
SELECT
MONTHNAME(t.summaryDateTime) as month, YEAR(t.summaryDateTime) as year
FROM
trading_summary t
GROUP BY EXTRACT(YEAR_MONTH FROM t.summaryDateTime) DESC";
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