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What is a Context Free Grammar?
... language is just a set (mathematical term for a collection of objects) of strings (sequences of symbols... very similar to the programming usage of the word "string"). A simple example of a formal language is the set of all binary strings of length three, {000, 001, 010, 011, 100, 101, 110, 111}.
...
SQLite - UPSERT *not* INSERT or REPLACE
...e columns in the table: ID, NAME, ROLE
BAD: This will insert or replace all columns with new values for ID=1:
INSERT OR REPLACE INTO Employee (id, name, role)
VALUES (1, 'John Foo', 'CEO');
BAD: This will insert or replace 2 of the columns... the NAME column will be set to NULL or the def...
How to change a table name using an SQL query?
...
Use sp_rename:
EXEC sp_rename 'Stu_Table', 'Stu_Table_10'
You can find documentation on this procedure on MSDN.
If you need to include a schema name, this can only be included in the first parameter (that is, this cannot be use...
PyPy — How can it possibly beat CPython?
... an object can save you the need to do multiple pointer dereferences to finally arrive at the method you want to call.
Q2. Which Python implementation was used to implement PyPy?
The PyPy interpreter is implemented in RPython which is a statically typed subset of Python (the language and not the ...
What is the difference between isinstance('aaa', basestring) and isinstance('aaa', str)?
...
In Python versions prior to 3.0 there are two kinds of strings "plain strings" and "unicode strings". Plain strings (str) cannot represent characters outside of the Latin alphabet (ignoring details of code pages for simplicity). Unicode strings (unicode) can represent characters ...
detect key press in python?
...
Python has a keyboard module with many features. Install it, perhaps with this command:
pip3 install keyboard
Then use it in code like:
import keyboard # using module keyboard
while True: # making a loop
try: # used try so that if user pressed other than the given ...
How to send POST request in JSON using HTTPClient in Android?
...some of the terminology feel free.
public static HttpResponse makeRequest(String path, Map params) throws Exception
{
//instantiates httpclient to make request
DefaultHttpClient httpclient = new DefaultHttpClient();
//url with the post data
HttpPost httpost = new HttpPost(path);
...
Static Vs. Dynamic Binding in Java
...le in Java
public class StaticBindingTest {
public static void main(String args[]) {
Collection c = new HashSet();
StaticBindingTest et = new StaticBindingTest();
et.sort(c);
}
//overloaded method takes Collection argument
public Collection sort(Collection ...
passing argument to DialogFragment
...on(position);
Bundle args = new Bundle();
args.putString("tar_name", clickedObj.getNameTarife());
args.putString("fav_name", clickedObj.getName());
FragmentManager fragmentManager = getSupportFragmentManager();
TarifeDetayPopup userPopUp ...
Android : Check whether the phone is dual SIM
... TelephonyInfo telephonyInfo = TelephonyInfo.getInstance(this);
String imeiSIM1 = telephonyInfo.getImsiSIM1();
String imeiSIM2 = telephonyInfo.getImsiSIM2();
boolean isSIM1Ready = telephonyInfo.isSIM1Ready();
boolean isSIM2Ready = telephonyInfo.isSIM2Ready();
...