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Run a single migration file
...f the ruby file:
rails console
>> require "db/migrate/20090408054532_add_foos.rb"
>> AddFoos.up
Note: newer versions of rails may require AddFoos.new.up rather than AddFoos.up.
An alternative way (without IRB) which relies on the fact that require returns an array of class names:
sc...
Programmatically set the initial view controller using Storyboards
How do I programmatically set the InitialViewController for a Storyboard? I want to open my storyboard to a different view depending on some condition which may vary from launch to launch.
...
Why does volatile exist?
...ed 16 bit value as a semaphore to know when the other guy was done. Essentially we did this:
void waitForSemaphore()
{
volatile uint16_t* semPtr = WELL_KNOWN_SEM_ADDR;/*well known address to my semaphore*/
while ((*semPtr) != IS_OK_FOR_ME_TO_PROCEED);
}
Without volatile, the optimizer sees ...
Binding a WPF ComboBox to a custom list
...0">
<Grid>
<StackPanel>
<Button Click="Button_Click">asdf</Button>
<ComboBox ItemsSource="{Binding Path=PhonebookEntries}"
DisplayMemberPath="Name"
SelectedValuePath="Name"
SelectedValue="{Binding...
How do you iterate through every file/directory recursively in standard C++?
...e to the standard.
An example, taken straight from the website:
bool find_file( const path & dir_path, // in this directory,
const std::string & file_name, // search for this name,
path & path_found ) // placing path here if found
{
...
Proper package naming for testing with the Go language
...
I forked a package and made changes, and now my tests are all trying to import the original repo instead of my forked package. With Strategy 3, I don't have to change the "github.com/original/link" to "github.com/my/fork", because it's just referencing '.' instead.
...
What MIME type should I use for CSV?
...reate a file with the .csv extension no matter which delimiter is used and PHP - as the most used server-side language- uses the term CSV in it's functions only, too. Call it "character separated files" and you're fine ;)
– mgutt
Oct 29 '18 at 13:41
...
What's the difference between ES6 Map and WeakMap?
...e: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap):
Keys of WeakMaps are of the type Object only. Primitive data types as
keys are not allowed (e.g. a Symbol can't be a WeakMap key).
Nor can a string, number, or boolean be used as a WeakMap key. A M...
What happens when there's insufficient memory to throw an OutOfMemoryError?
...
The JVM never really runs out of memory. It does memory computation of the heap stack in advance.
The Structure of the JVM, Chapter 3, section 3.5.2 states:
If Java virtual machine stacks can be dynamically expanded, and expansion is...
Smart way to truncate long strings
...
Essentially, you check the length of the given string. If it's longer than a given length n, clip it to length n (substr or slice) and add html entity &hellip; (…) to the clipped string.
Such a method looks like
function tru...