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How to check if an object is nullable?
... boxed Nullable<T> but because I was writing a generic WPF converter base class and some properties are nullable, so I used Nullable.GetUnderlyingType to detect that case and Activator.CreateInstance to make a boxed nullable, (Convert.ChangeType doesn't handle nullables btw).
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Approximate cost to access various caches and main memory?
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Surely these care very HUGE amounts, based on processor design, ram latency/frequency, hard disk caching(both type and size)/rpm etc etc? To Quote INTEL (for values they released for one specific CPU):"NOTE:These values are rough approximations. They depend on C...
Understanding the difference between Object.create() and new SomeFunction()
.... :) But SmallTalk certainly followed it. … And OOP does not equal class-based OOP.. JS is prototype-based OOP, but they all have OOP in common. In fact JS’s OOP philosophy is much cleaner, more elegant and more universal than the class-based approach. They just failed to implement it nicely too...
Single Sign On across multiple domains [closed]
...the script client_login.php
All the domains have a shared user session database.
When the client domain requires the user to be logged in, it redirects to the master domain (login.mydomain.com/master_login.php). If the user has not signed in to the master it requests authentication from the user (ie...
How To Create a Flexible Plug-In Architecture?
...- configuration files (XML, .conf, and so on), inheritance frameworks, database information, libraries, and others. In my experience:
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Order data frame rows according to vector with specific order
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not sure it is the cleanest way, but with only "base" functions, this should work if you have duplicates in df: df <- data.frame(name=letters[c(1:4, 1:4)], value=c(rep(TRUE, 2), rep(FALSE, 2),rep(TRUE, 2), rep(FALSE, 2) )) target <- c("b", "c", "a", "d") df[order...
How does MongoDB sort records when no sort order is specified?
...n a Mongo find() query without any sort order specified, what does the database internally use to sort the results?
2 Answe...
Using Auto Layout in UITableView for dynamic cell layouts & variable row heights
... view automatically asks each cell what height its contentView needs to be based on the known fixed width of the content view (which is based on the table view's width, minus any additional things like a section index or accessory view) and the auto layout constraints you have added to the cell's co...
Do we still need end slashes in HTML5?
...re Void Elements so they do not need an end tag.
Void elements
area, base, br, col, command, embed, hr, img, input, keygen, link, meta, param, source, track, wbr
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Void elements only have a start tag; end tags must not be specified for void elements.
W3C | WHATWG
That being said it...
What is the difference between google tag manager and google analytics?
...rts about activity on your site. GTM is a tag manager that can output tags based on defined rules. So for example, you can either implement your GA code on your site directly, or you can implement the GTM code and use GTM to output the GA code.
The main benefit of GTM (or any tag manager worth an...