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Python: print a generator expression?
...e generator expression into a list comprehension. It's the same thing and calling list() on it. So the way to make a generator expression into a list is to put brackets around it.
Detailed explanation:
A generator expression is a "naked" for expression. Like so:
x*x for x in range(10)
Now, you ...
Is there a REAL performance difference between INT and VARCHAR primary keys?
... and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
14 Answers
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String concatenation: concat() vs “+” operator
...then throwing it away when you create the final String. In practice memory allocation is surprisingly fast.
Update: As Pawel Adamski notes, performance has changed in more recent HotSpot. javac still produces exactly the same code, but the bytecode compiler cheats. Simple testing entirely fails bec...
How do I execute any command editing its file (argument) “in place” using bash?
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This is an answer. I was actually wondering if there is a generic solution to this problem. For example if I want to find all UNIQ lines in a file "in place", I can't do -o
– jm.
Sep 28 '08 at 21:45
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Dashed line border around UIView
...t@2x.png and test@3x.png with size of 240x240 and 360x360 which is used in all the apple device automatically with it's related name. (i.e. test.png is use in iPhone 4, test@2x will useful for iPhone 4s, 5, 5s, 6, 6s and twst@3x will useful for iPhone 6 plus, 6s plus.
– Paras J...
How to find out element position in slice?
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this does not find the original index; rather it loses all the indexes by re-ordering them
– newacct
Nov 29 '11 at 20:16
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In Python, how do I determine if an object is iterable?
...e a method like isiterable ? The only solution I have found so far is to call
21 Answers
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Check if at least two out of three booleans are true
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Logger slf4j advantages of formatting with {} instead of string concatenation
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It is about string concatenation performance. It's potentially significant if your have dense logging statements.
(Prior to SLF4J 1.7) But only two parameters are possible
Because the vast majority of logging statements have 2 or fewer parameters, so SLF4J API up to version 1....
Signed to unsigned conversion in C - is it always safe?
...herwise, if the type of the operand with signed integer type can represent all of the values of the type of the operand with unsigned integer type, then the operand with unsigned integer type is converted to the type of the operand with signed integer type.
Otherwise, both operands are converted t...