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Is C++ context-free or context-sensitive?
... is (probably) Turing-complete, since it shows a program which is syntactically correct if and only if a given integer is prime.
So I assert that C++ is neither context-free nor context-sensitive.
If you allow arbitrary symbol sequences on both sides of any production, you produce an Type-0 gramma...
How can I check for an empty/undefined/null string in JavaScript?
...n do
if (strValue) {
//do something
}
If you need to check specifically for an empty string over null, I would think checking against "" is your best bet, using the === operator (so that you know that it is, in fact, a string you're comparing against).
if (strValue === "") {
//...
}
...
How do I trim a file extension from a String in Java?
...have Apache Commons I/O already in your project, that's right. But if this all you need from it, you're adding (at least) 2.5 MB of dead weight to your project for something that can be easily done with a single line.
– foo
Sep 3 '18 at 9:40
...
How to check if a String contains only ASCII?
The call Character.isLetter(c) returns true if the character is a letter. But is there a way to quickly find if a String only contains the base characters of ASCII?
...
What are the differences between git remote prune, git prune, git fetch --prune, etc
...frustrated about this. The best way to look at is this. There are potentially three versions of every remote branch:
The actual branch on the remote repository
(e.g., remote repo at https://example.com/repo.git, refs/heads/master)
Your snapshot of that branch locally (stored under refs/remotes/...
Password masking console application
...comments, and modifying it to use SecureString instead of String, test for all control keys, and not error or write an extra "*" to the screen when the password length is 0, my solution is:
public static SecureString getPasswordFromConsole(String displayMessage) {
SecureString pass = new Secure...
What does “default” mean after a class' function declaration?
...pecify that you don't want the compiler to generate that function automatically.
With the introduction of move constructors and move assignment operators, the rules for when automatic versions of constructors, destructors and assignment operators are generated has become quite complex. Using = defa...
How to deploy an ASP.NET Application with zero downtime
...
You need 2 servers and a load balancer. Here's in steps:
Turn all traffic on Server 2
Deploy on Server 1
Test Server 1
Turn all traffic on Server 1
Deploy on Server 2
Test Server 2
Turn traffic on both servers
Thing is, even in this case you will still have application restarts and lo...
Chmod 777 to a folder and all contents [duplicate]
I have a web directory /www and a folder in that directory called store .
7 Answers
...
How to make “if not true condition”?
... then ....
OR
if (( ! $(grep -c "sysa" /etc/passwd) )) ; then ....
Finally, there is an award called the Useless Use of Cat (UUOC). :-) Some people will jump up and down and cry gothca! I'll just say that grep can take a file name on its cmd-line, so why invoke extra processes and pipe construc...