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How to check that an object is empty in PHP?
...g doesn't work for me, because I get the error: PHP Parse error: syntax error, unexpected '(array)' (array) (T_ARRAY_CAST) in ... I use PHP version 5.4.28 and the first option with two lines of code works for me.
– Coanda
May 18 '14 at 13:34
...
Why can't I use a list as a dict key in python?
...e on the topic in the Python wiki: Why Lists Can't Be Dictionary Keys. As explained there:
What would go wrong if you tried to use lists as keys, with the hash as, say, their memory location?
It can be done without really breaking any of the requirements, but it leads to unexpected behavior. L...
Does pandas iterrows have performance issues?
...ernally by pandas, though it depends on what is going on inside the apply expression. For example, df.apply(lambda x: np.sum(x)) will be executed pretty swiftly, though of course, df.sum(1) is even better. However something like df.apply(lambda x: x['b'] + 1) will be executed in Python space, and co...
Getting attributes of Enum's value
... to get attributes of the enum values and not of the enum itself? For example, suppose I have the following enum :
24 ...
Difference between “or” and || in Ruby? [duplicate]
...
Here's a ruby operator precedence table.
See this question for another example using and/&&.
Also, be aware of some nasty things that could happen:
a = false || true #=> true
a #=> true
a = false or true #=> true
a #=> false
Both of the previous two statements evalua...
TINYTEXT, TEXT, MEDIUMTEXT, and LONGTEXT maximum storage sizes
Per the MySQL docs , there are four TEXT types:
4 Answers
4
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What does “not run” mean in R help pages?
...
"not run" encloses code that shouldn't be executed in the example function (e.g. time-consuming code parts, user-interaction, ...).
see e.g. ?example:
As detailed in the manual Writing R Extensions, the author of
the help page can markup parts of the examples for tw...
What's the reason I can't create generic array types in Java?
... But what about erasure? Why doesn't that apply?
– Qix - MONICA WAS MISTREATED
Mar 5 '13 at 8:22
15
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How to change identity column values programmatically?
...following structure
CREATE TABLE Test
(
ID INT IDENTITY(1,1) PRIMARY KEY,
X VARCHAR(10)
)
INSERT INTO Test
OUTPUT INSERTED.*
SELECT 'Foo' UNION ALL
SELECT 'Bar' UNION ALL
SELECT 'Baz'
Then you can do
/*Define table with same structure but no IDENTITY*/
CREATE TABLE Temp
(
ID INT PRIMARY KEY,
X...
Hide keyboard when scroll UITableView
...
For those who forgets, you still needs to make UITextfield resign first responder.
– skyline75489
Dec 23 '15 at 4:04
1
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