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Is it possible for a computer to “learn” a regular expression by user-provided examples?
...ton, it is possible to learn some regular expressions by a program. Kearns and Valiant show some cases where it is not possible to learn a finite automaton. A related problem is learning hidden Markov Models, which are probabilistic automata that can describe a character sequence. Note that most mod...
RabbitMQ and relationship between channel and connection
... a Channel are serialized, with only one thread being able to run a
command on the Channel at a time. Even so, applications should prefer
using a Channel per thread instead of sharing the same Channel across
multiple threads.
There is no direct relation between Channel and Queue. A Channel ...
Vim for Windows - What do I type to save and exit from a file?
...lly typed git commit -a instead of git commit -am "My commit message" , and now I'm viewing my CMD prompt filled with the file version of my commit message ("Please enter the commit message for your..."). I've added my message to the top, but now I can't figure out how to save and leave. I tried ...
HTTP Basic Authentication credentials passed in URL and encryption
I have a question about HTTPS and HTTP Authentication credentials.
3 Answers
3
...
Most efficient way to check for DBNull and then assign to a variable?
...to avoid. By writing row.IsNull(columnName) you're reading it once already and reading it again. Not saying that will make a difference, but theoretically it can be less efficient..
– nawfal
Feb 6 '13 at 16:31
...
How to export and import environment variables in windows?
...n different machines. I just want to export the settings from one computer and import to other ones.
7 Answers
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Why is extending native objects a bad practice?
... get a perfomance hit? Do they fear that somebody does it "the wrong way", and adds enumerable types to Object , practically destroying all loops on any object?
...
How to check if hex color is “too black”?
...e darkness of a color chosen by a color picker to see if it's "too black", and if so, set it to white. I thought I could use the first characters of the hex value to pull this off. It's working, but it's switching some legitimately "light" colors too.
...
What exactly is Spring Framework for? [closed]
...The problem
For example, suppose you need to list the users of the system and thus declare an interface called UserLister:
public interface UserLister {
List<User> getUsers();
}
And maybe an implementation accessing a database to get all the users:
public class UserListerDB implements...
What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?
...
Braces ($var vs. ${var})
In most cases, $var and ${var} are the same:
var=foo
echo $var
# foo
echo ${var}
# foo
The braces are only needed to resolve ambiguity in expressions:
var=foo
echo $varbar
# Prints nothing because there is no variable 'varbar'
echo ${var}bar...