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Django: multiple models in one template using forms [closed]
...his since 'and' short circuits and we want to check to whole page for form errors
if a_valid and b_valid and c_valid:
a = formA.save()
b = formB.save(commit=False)
c = formC.save(commit=False)
b.foreignkeytoA = a
b.save()
c.foreignkeytoB = b
...
Why does this code using random strings print “hello world”?
...
}
catch (IOException e) {
System.err.println("Error reading from " + fileName + ": " + e);
}
}
private static boolean isLowerAlpha (String word) {
char[] c = word.toCharArray();
for (int i = 0; i < c.length; i++) {
if (c[i]...
What's the difference between and
...boolean instanceTest = aList instanceof List<?>;
but this gives an error
List aList = new ArrayList<>();
boolean instancetest = aList instanceof List<? extends Object>;
for more info read Java generics and collections by Maurice Naftalin
...
What makes JNI calls slow?
...s are specified in strings and queried from the JVM. This is both slow and error-prone.
Java Strings are objects, have length and are encoded. Accessing or creating a string may require an O(n) copy.
Some additional discussion, possibly dated, can be found in "Java¿ Platform Performance: Strategi...
Cannot install packages using node package manager in Ubuntu
...
This also fixed error above for me. It is much better for nodejs developer (in my view the whole developers, i am not one who work in nodejs). I did use it.
– Ajeeb.K.P
Jan 22 '15 at 7:42
...
Passing enum or object through an intent (the best solution)
...by tedzyc about the fact that the solution provided by Oderik gives you an error. However, the alternative offered is a bit cumbersome to use (even using generics).
If you are really worried about the performance of adding the enum to an Intent I propose these alternatives instead:
OPTION 1:
publ...
Random float number generation
...so be careful with division by zero at (N-M). A nice way to deal with this error is found here: stackoverflow.com/questions/33058848/…
– DrBeco
May 26 '18 at 4:42
add a comm...
Android, ListView IllegalStateException: “The content of the adapter has changed but ListView did no
...ork the benefit of the doubt on this one and say that it is most likely an error in your code. I hope this helps. Maybe you can adapt it to your list and data.
public class ListViewStressTest extends ListActivity {
ArrayAdapter<String> adapter;
ListView list;
AsyncTask<Void, St...
How to re import an updated package while in Python Interpreter? [duplicate]
I often test my module in the Python Interpreter, and when I see an error, I quickly update the .py file. But how do I make it reflect on the Interpreter ? So, far I have been exiting and reentering the Interpreter because re importing the file again is not working for me.
...
How does “cat
...f the variable PS2, processed as described in Shell Variables, to standard error before reading each line of input until the delimiter has been recognized.
Examples
Some examples not yet given.
Quotes prevent parameter expansion
Without quotes:
a=0
cat <<EOF
$a
EOF
Output:
0
With qu...