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C# : 'is' keyword and checking for Not
...ublic static bool IsA<T>(this object obj) {
return obj is T;
}
and then use it to:
if (!child.IsA<IContainer>())
And you could follow on your theme:
public static bool IsNotAFreaking<T>(this object obj) {
return !(obj is T);
}
if (child.IsNotAFreaking<IContainer&g...
How do I do base64 encoding on iOS?
I'd like to do base64 encoding and decoding, but I could not find any support from the iPhone SDK . How can I do base64 encoding and decoding with or without a library?
...
What makes Lisp macros so special?
...not had the privilege of using Lisp macros. As someone who wants to understand the buzz, please explain what makes this feature so powerful.
...
Extract a substring according to a pattern
...we create a data frame with two columns, one for the part before the colon and one for after, and then extract the latter.
library(dplyr)
library(tidyr)
library(purrr)
DF <- data.frame(string)
DF %>%
separate(string, into = c("pre", "post")) %>%
pull("post")
## [1] "E001" "E002" "E00...
Reduce, fold or scan (Left/Right)?
... operator's two arguments). This way we can cumulate a result.
reduceLeft and reduceRight cumulate a single result.
foldLeft and foldRight cumulate a single result using a start value.
scanLeft and scanRight cumulate a collection of intermediate cumulative results using a start value.
Accumulate...
Convert string to number and add one
I want to turn the value I get from the id into a number and add one to it then pass the new value into the dosomething() function to use. When I tried this and the value is one I get back 11 not 2.
...
Mismatch Detected for 'RuntimeLibrary'
I downloaded and extracted Crypto++ in C:\cryptopp. I used Visual Studio Express 2012 to build all the projects inside (as instructed in readme), and everything was built successfully. Then I made a test project in some other folder and added cryptolib as a dependency. After that, I added the includ...
Database Design for Revisions?
...tribute. This just causes problems down the line, requires surrogate keys and all sorts of other problems.
Design 2 does have problems with schema changes. If you change the Employees table you have to change the EmployeeHistories table and all the related sprocs that go with it. Potentially doub...
Find if current time falls in a time range
...ount the number of matches? For example I want to count how many saturdays and sundays are in the range.
– pbies
Sep 4 '13 at 19:28
...
Flat file databases [closed]
...gt; array("dubayou.com","willwharton.com","codecream.com"),
"and_one" => "more");
and to save or update the db record for that user.
$dir = "../userdata/"; //make sure to put it bellow what the server can reach.
file_put_contents($dir.$user['name'],serialize($user));
and to lo...