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How do you echo a 4-digit Unicode character in Bash?
...d like to add the Unicode skull and crossbones to my shell prompt (specifically the 'SKULL AND CROSSBONES' (U+2620)), but I can't figure out the magic incantation to make echo spit it, or any other, 4-digit Unicode character. Two-digit one's are easy. For example, echo -e "\x55", .
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Python argparse mutual exclusive group
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add_mutually_exclusive_group doesn't make an entire group mutually exclusive. It makes options within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd have:
p...
Django rest framework nested self-referential objects
... the `subcategories` field
return CategorySerializer()
Actually, as you've noted the above isn't quite right.
This is a bit of a hack, but you might try adding the field in after the serializer is already declared.
class CategorySerializer(serializers.ModelSerializer):
parentCat...
Checking a Python module version at runtime
...s have an attribute which holds the version information for the module (usually something like module.VERSION or module.__version__ ), however some do not.
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How do you manage databases in development, test, and production?
...of good options. I wouldn't use the "restore a backup" strategy.
Script all your schema changes, and have your CI server run those scripts on the database. Have a version table to keep track of the current database version, and only execute the scripts if they are for a newer version.
Use a migr...
Importing from a relative path in Python
...his method is still commonly used in some situations, where you aren't actually ever 'installing' your package. For example, it's popular with Django users.
You can add Common/ to your sys.path (the list of paths python looks at to import things):
import sys, os
sys.path.append(os.path.join(os.p...
Call Go functions from C
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You can call Go code from C. it is a confusing proposition though.
The process is outlined in the blog post you linked to. But I can see how that isn't very helpful. Here is a short snippet without any unnecessary bits. It should ma...
C# Sortable collection which allows duplicate keys
... Use this Comparer e.g. with SortedLists or SortedDictionaries, that don't allow duplicate keys
/// </summary>
/// <typeparam name="TKey"></typeparam>
public class DuplicateKeyComparer<TKey>
:
IComparer<TKey> where TKey : IComparable
{
#...
How to read/process command line arguments?
I am originally a C programmer. I have seen numerous tricks and "hacks" to read many different arguments.
17 Answers
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Rails Root directory path?
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Personally I like the newer syntax: Rails.root / 'app' / 'assets' / 'images' / 'logo.png'
– Ajedi32
Feb 18 '16 at 17:13
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