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Javascript regex returning true.. then false.. then true.. etc [duplicate]
.... In JavaScript, global regexen have state: you call them (with exec, test etc.) the first time, you get the first match in a given string. Call them again and you get the next match, and so on until you get no match and it resets to the start of the next string. You can also write regex.lastIndex= ...
How to import a Python class that is in a directory above?
... exists. Two dots means up one package level. Three dots is up two levels, etc. So if you execute from . import mod from a module in the pkg package then you will end up importing pkg.mod. If you execute from ..subpkg2 import mod from within pkg.subpkg1 you will import pkg.subpkg2.mod. The specifica...
How to display all methods of an object?
...ertyNames(Math));
//-> ["E", "LN10", "LN2", "LOG2E", "LOG10E", "PI", ...etc ]
You can then use filter() to obtain only the methods:
console.log(Object.getOwnPropertyNames(Math).filter(function (p) {
return typeof Math[p] === 'function';
}));
//-> ["random", "abs", "acos", "asin", "atan"...
Error to run Android Studio
...javac 1.8.0_91
Finally, add JAVA_HOME to the environment variable
Edit /etc/environment and add JAVA_HOME=/usr/lib/jvm/java-8-oracle to the end of the file
sudo nano /etc/environment
Append to the end of the file
JAVA_HOME=/usr/lib/jvm/java-8-oracle
You will then have to reboot, you can do ...
Class method differences in Python: bound, unbound and static
...
where
self is the CPO (it could be an instance of list, str, function etc) and is supplied by the runtime
instance is the instance of the class where this CPO is defined (the object 'c' above) and needs to be explicity supplied by us
owner is the class where this CPO is defined(the class object...
What are the most common naming conventions in C?
...typically are in lower case (in my experience) rather than the C++/Java/C#/etc convention of making the first letter a capital but I guess it's possible in C too.
C++ is more complex. I've seen a real mix here. Camel case for class names or lowercase+underscores (camel case is more common in my ex...
How to install trusted CA certificate on Android device?
...rsion Gingerbread & Froyo, there was a single read-only file ( /system/etc/security/cacerts.bks ) containing the trust store with all the CA ('system') certificates trusted by default on Android. Both system apps and all applications developed with the Android SDK use this. Use these instruction...
Adding a directory to $LOAD_PATH (Ruby)
...tyle Guide says to "Avoid using Perl-style special variables (like $:, $;, etc. ). They are quite cryptic and their use in anything but one-liner scripts is discouraged."
– bobmagoo
Sep 19 '15 at 21:06
...
What is a plain English explanation of “Big O” notation?
... have polynomial complexity or is solvable in polynomial time.
O(n), O(n2) etc. are all polynomial time. Some problems cannot be solved in polynomial time. Certain things are used in the world because of this. Public Key Cryptography is a prime example. It is computationally hard to find two prime f...
What is your naming convention for stored procedures? [closed]
...o search 50 odd Add procedures for the Product add, and 50 odd for the Get etc.
Because of this in my new application I'm planning on grouping procedure names by object, I'm also dropping the usp as I feel it is somewhat redundant, other than to tell me its a procedure, something I can deduct from ...