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Impossible to Install PG gem on my mac with Mavericks
I'm trying to install the pg gem in order to work again with my rails projects. But I get this error:
26 Answers
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What's the (hidden) cost of Scala's lazy val?
...nswered Jun 15 '10 at 7:51
oxbow_lakesoxbow_lakes
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Scala how can I count the number of occurrences in a list
...", "banana", "apple", "oranges", "oranges")
s.groupBy(identity).mapValues(_.size)
giving a Map with a count for each item in the original sequence:
Map(banana -> 1, oranges -> 3, apple -> 3)
The question asks how to find the count of a specific item. With this approach, the solution w...
See line breaks and carriage returns in editor
Does anyone know of a text editor on Linux that allows me to see line breaks and carriage returns? Does Vim support this feature?
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Non-alphanumeric list order from os.listdir()
...however you want. Based on what you describe,
sorted(os.listdir(whatever_directory))
Alternatively, you can use the .sort method of a list:
lst = os.listdir(whatever_directory)
lst.sort()
I think should do the trick.
Note that the order that os.listdir gets the filenames is probably complet...
Difference between “git checkout ” and “git checkout -- ”
...his is not Git-specific, it's a general Unix command line convention. Normally you use it to clarify that an argument is a file name rather than an option, e.g.
rm -f # does nothing
rm -- -f # deletes a file named "-f"
git checkout1 also takes -- to mean that subsequent arguments are not ...
How to set -source 1.7 in Android Studio and Gradle
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This is essentially the same as the accepted answer.
– Kerem
Aug 12 '15 at 12:20
1
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Auto-fit TextView for Android
...de
public void onClick(final View v) {
container.removeAllViews();
final int maxWidth = container.getWidth();
final int maxHeight = container.getHeight();
final AutoResizeTextView fontFitTextView = new AutoResizeTextView(MainActivity.this);
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Concurrent.futures vs Multiprocessing in Python 3
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I wouldn't call concurrent.futures more "advanced" - it's a simpler interface that works very much the same regardless of whether you use multiple threads or multiple processes as the underlying parallelization gimmick.
So, like virtuall...
How to 'bulk update' with Django?
...ings like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelClass.save method (so if you have some logic inside it won't be triggered).
No django signals will be emitte...