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Kotlin Ternary Conditional Operator
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You could define your own Boolean extension function that returns null when the Boolean is false to provide a structure similar to the ternary operator:
infix fun <T> Boolean.then(param: T): T? = if (this) param else null
This would make an a ? b : c expressio...
Error when trying to obtain a certificate: The specified item could not be found in the keychain
...k, or the default will include whatever's in the brackets [].
Common Name (CN) should be your private key name (e.g., John Doe Dev Key)
Email Address should be your email address (e.g. thon@example.com)
Everything else should be blank
Verify your CSR
$ openssl req -noout -text -in Certificates.cs...
passing several arguments to FUN of lapply (and others *apply)
I have a question regarding passing multiple arguments to a function, when using lapply in R .
4 Answers
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Detect if value is number in MySQL
...l1 * 1) = col1
It doesn't work for non-standard numbers like
1e4
1.2e5
123. (trailing decimal)
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C++ performance challenge: integer to std::string conversion
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Ah, awesome challenge by the way... I've had a lot of fun with this.
I have two algorithms to submit (code is at the bottom if you feel like skipping to it). In my comparisons I require that the function return a string and that it can handle int and unsigned int. Comparing thi...
Reading binary file and looping over each byte
... example uses a chunksize of 8192 Bytes. The parameter for the file.read()-function simply specifies the size, i.e. the number of Bytes to be read. codeape chose 8192 Byte = 8 kB (actually it's KiB but that's not as commonly known). The value is "totally" random but 8 kB seems to be an appropriate v...
Is there a way to pass optional parameters to a function?
Is there a way in Python to pass optional parameters to a function while calling it and in the function definition have some code based on "only if the optional parameter is passed"
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How to compile a static library in Linux?
...e lib
#include <stdio.h>
#include "lib.h"
int main ( void )
{
fun1(10);
fun2(10);
return 0;
}
lib.h the libs main header
#ifndef LIB_H_INCLUDED
#define LIB_H_INCLUDED
#include "lib1.h"
#include "lib2.h"
#endif
lib1.c first lib source
#include "lib1.h"
#include <stdio...
MySQL Conditional Insert
...nsert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = 123
AND item = 456)
In this, dual is a table with one row only (found orig...