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Rails: Using build with a has_one association in rails
In this example, I create a user with no profile , then later on create a profile for that user. I tried using build with a has_one association but that blew up. The only way I see this working is using has_many . The user is supposed to only have at most one profile .
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Create list of single item repeated N times
...ts, all of varying lengths. Each list will contain the same element e , repeated n times (where n = length of the list).
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Anonymous recursive PHP functions
Is it possible to have a PHP function that is both recursive and anonymous? This is my attempt to get it to work, but it doesn't pass in the function name.
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Can an enum class be converted to the underlying type?
Is there a way to convert an enum class field to the underlying type? I thought this would be automatic, but apparently not.
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Convert Go map to json
I tried to convert my Go map to a json string with encoding/json Marshal, but it resulted in a empty string.
3 Answers
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SQLite Concurrent Access
Does SQLite3 safely handle concurrent access by multiple processes
reading/writing from the same DB? Are there any platform exceptions to that?
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Convert data.frame column format from character to factor
...cars) #allows you to see the classes of the variables (all numeric)
#one approach it to index with the $ sign and the as.factor function
mtcars$am <- as.factor(mtcars$am)
#another approach
mtcars[, 'cyl'] <- as.factor(mtcars[, 'cyl'])
str(mtcars) # now look at the classes
This also works f...
Where in memory are my variables stored in C?
By considering that the memory is divided into four segments: data, heap, stack, and code, where do global variables, static variables, constant data types, local variables (defined and declared in functions), variables (in main function), pointers, and dynamically allocated space (using malloc and ...
Golang: How to pad a number with zeros when printing?
How can I print a number or make a string with zero padding to make it fixed width?
6 Answers
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git replacing LF with CRLF
Running git on a Windows XP machine, using bash. I exported my project from SVN, and then cloned a bare repository.
20 Answ...