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LINQ's Distinct() on a particular property
... LINQ as it stands, although it's fairly easy to write:
public static IEnumerable<TSource> DistinctBy<TSource, TKey>
(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)
{
HashSet<TKey> seenKeys = new HashSet<TKey>();
foreach (TSource e...
“Private” (implementation) class in Python
...now the underscore rule extended to classes. I do not want to clutter my namespace when importing, so this behavior is what I was looking for. Thanks!
– oparisy
Feb 15 '09 at 19:52
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Find current directory and file's directory [duplicate]
...contained in, write this in that file:
import os
dir_path = os.path.dirname(os.path.realpath(__file__))
(Note that the incantation above won't work if you've already used os.chdir() to change your current working directory, since the value of the __file__ constant is relative to the current work...
How do I insert NULL values using PDO?
...Param takes a variable, to reference, and doesn't pull in a value at the time of calling bindParam. I found this in a comment on the php docs:
bindValue(':param', null, PDO::PARAM_INT);
EDIT: P.S. You may be tempted to do this bindValue(':param', null, PDO::PARAM_NULL); but it did not work for ev...
Any reason why scala does not explicitly support dependent types?
...e combination of singleton types, path-dependent types and implicit values means that Scala has surprisingly good support for dependent typing, as I've tried to demonstrate in shapeless.
Scala's intrinsic support for dependent types is via path-dependent types. These allow a type to depend on a sel...
Ignore mapping one property with Automapper
...e the following scenario:
Class OrderModel has a property called 'ProductName' that isn't in the database.
So when I try to do the mapping with:
...
How do I clone a job in Jenkins?
...eed to clone the existing jobs pointing to the other branch so that this same workflow occurs and builds are performed on every commit. Can somebody explain how I would clone these jobs? I don't seem to see a way to do it through the UI nor can I even see a way to list the jobs out through the UI.
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How to disable Crashlytics during development
... for the debug version.
Wrap the call to Crashlytics.start() in an if statement that checks a debug flag. You could use either a custom flag or an approach like the ones proposed here: How to check if APK is signed or "debug build"?
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Is it possible to capture a Ctrl+C signal and run a cleanup function, in a “defer” fashion?
...pture the Ctrl+C ( SIGINT ) signal sent from the console and print out some partial run totals.
10 Answers
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How to select all records from one table that do not exist in another table?
...
SELECT t1.name
FROM table1 t1
LEFT JOIN table2 t2 ON t2.name = t1.name
WHERE t2.name IS NULL
Q: What is happening here?
A: Conceptually, we select all rows from table1 and for each row we attempt to find a row in table2 with the same ...