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Should I Stop Stopwatch at the end of the method?
... It doesn't prevent anything, he's creating the stopwatch in the method and not returning it, so he won't be able to get a hold of it later to "make mistakes with".
– Ronan Thibaudau
Jun 10 '14 at 12:23
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Turning multi-line string into single comma-separated
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You can use awk and sed:
awk -vORS=, '{ print $2 }' file.txt | sed 's/,$/\n/'
Or if you want to use a pipe:
echo "data" | awk -vORS=, '{ print $2 }' | sed 's/,$/\n/'
To break it down:
awk is great at handling data broken down into fi...
Unique fields that allow nulls in Django
...trings are equal to empty strings for uniqueness checks, under both Django and database rules.
You can force the admin interface to store NULL for an empty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None:
class FooForm(forms....
Truncating long strings with CSS: feasible yet?
Is there any good way of truncating text with plain HTML and CSS, so that dynamic content can fit in a fixed-width-and-height layout?
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Java using enum with switch statement
...about this:
Use a list of static final ints rather than a type-safe enum and switch on the int value you receive (this is the pre-Java 5 approach)
Switch on either a specified id value (as described by heneryville) or the ordinal value of the enum values; i.e. guideView.GUIDE_VIEW_SEVEN_DAY.ordina...
Difference in months between two dates
...ssuming the day of the month is irrelevant (i.e. the diff between 2011.1.1 and 2010.12.31 is 1), with date1 > date2 giving a positive value and date2 > date1 a negative value
((date1.Year - date2.Year) * 12) + date1.Month - date2.Month
Or, assuming you want an approximate number of 'average...
How to set size for local image using knitr for markdown?
...ge that I would like to include in an .Rmd file which I will then knit and convert to HTML slides with Pandoc . Per this post , this will insert the local image :
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Unresolved external symbol on static class members
.../stackoverflow.com/a/11711082/55721)
If using older versions of the C++ standard, you must add the definitions to match your declarations of X and Y
unsigned char test::X;
unsigned char test::Y;
somewhere. You might want to also initialize a static member
unsigned char test::X = 4;
and again, yo...
What is a database transaction?
... To do that you have first to withdraw the amount from the source account, and then deposit it to the destination account. The operation has to succeed in full. If you stop halfway, the money will be lost, and that is Very Bad.
In modern databases transactions also do some other things - like ensur...
When should i use npm with “-g” flag and why?
...g npm for js package management recently. Although I do have a fair understanding of package management in different enivronments(lets say using apt, rvm/gem, pythonbrew/virtualenv/pip), I don't quite understand how npm fully fits in.
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