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Default string initialization: NULL or Empty? [closed]
... strings to NULL, with the thinking that NULL means the absence of a value and "" or String.Empty is a valid value. I have seen more examples lately of code where String.Empty is considered the default value or represents no value. This strikes me as odd, with the newly added nullable types in c# ...
C++ where to initialize static const
...// No definition for i. (*)
const int foo::j = 4;
(*) According to the standards you must define i outside of the class definition (like j is) if it is used in code other than just integral constant expressions. See David's comment below for details.
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Increase number of axis ticks
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You can override ggplots default scales by modifying scale_x_continuous and/or scale_y_continuous. For example:
library(ggplot2)
dat <- data.frame(x = rnorm(100), y = rnorm(100))
ggplot(dat, aes(x,y)) +
geom_point()
Gives you this:
And overriding the scales can give you something like...
iOS Equivalent For Android Shared Preferences
I am porting an Android app to iOS, one thing I used was the Shared Preferences in Android to save each time a level was complete.
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How to pull a random record using Django's ORM?
... of them: newest, one that was not visited for most time, most popular one and a random one.
15 Answers
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PDO Prepared Inserts multiple rows in single query
...a.
With prepared inserts you need to know the fields you're inserting to, and the number of fields to create the ? placeholders to bind your parameters.
insert into table (fielda, fieldb, ... ) values (?,?...), (?,?...)....
That is basically how we want the insert statement to look like.
Now, t...
How do I increase the scrollback buffer in a running screen session?
...with through putty. I've realized that the scrollback buffer is too small and would like to increase it without starting a new screen session.
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Renaming projects in Xcode 4
...d to do is click twice slowly on the project root in the project navigator and it then becomes editable. After you rename the project and press 'enter' it will suggest to automatically change all project-name-related entries and will allow you to de-select some of them if you want.
Nice.
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schema builder laravel migrations unique on two columns
...lso somehow missed the fact the second param is to manually name the index and I had an automatically generated index name which was too long. Thank you, man! +1
– Ciprian Mocanu
Feb 2 '16 at 9:04
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Thymeleaf: how to use conditionals to dynamically add/remove a CSS class
...ou could just inject the desired class into the model from the controller, and then have th:classappend="${theRightClass}"
– demaniak
Sep 7 '17 at 14:30
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