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How to list the contents of a package using YUM?
... Why install a new package when you can use rpm -ql $PACKAGE_NAME?
– isapir
Apr 8 '19 at 17:42
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What is a higher kinded type in Scala?
...e used classes were defined as:
class String
class List[T]
class Functor[F[_]]
To avoid the indirection through defining classes, you need to somehow express anonymous type functions, which are not expressible directly in Scala, but you can use structural types without too much syntactic overhead (...
Weak and strong property setter attributes in Objective-C
...n release autorelease etc... Instead you use strong weak for properties or __strong
__weak
for variables (defaults to __strong). Strong is the equivalent to retain, however ARC will manage the release for you.
The only time you would want to use weak, is if you wanted to avoid retain cycles (e.g...
How to convert ActiveRecord results into an array of hashes
...
as_json
You should use as_json method which converts ActiveRecord objects to Ruby Hashes despite its name
tasks_records = TaskStoreStatus.all
tasks_records = tasks_records.as_json
# You can now add new records and return the...
Selecting multiple columns in a pandas dataframe
...ou can just return a view of only those columns by passing a list into the __getitem__ syntax (the []'s).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns)...
Why is  appearing in my HTML? [duplicate]
...
// Tell me the root folder path.
// You can also try this one
// $HOME = $_SERVER["DOCUMENT_ROOT"];
// Or this
// dirname(__FILE__)
$HOME = dirname(__FILE__);
// Is this a Windows host ? If it is, change this line to $WIN = 1;
$WIN = 0;
// That's all I need
?>
<!DOCTYPE html PUBLIC "-//W3C/...
What is the difference between C# and .NET?
...ment 0x00000200
.stackreserve 0x00100000
.subsystem 0x0003 // WINDOWS_CUI
.corflags 0x00000001 // ILONLY
// Image base: 0x05DB0000
// =============== CLASS MEMBERS DECLARATION ===================
.class public auto ansi beforefieldinit Example.Class1
extends [mscorlib]System.Objec...
Correct way to use _viewstart.cshtml and partial Razor views?
I'm using _viewstart.cshtml to automagically assign the same Razor Layout to my views.
1 Answer
...
A semantics for Bash scripts?
...s not terribly robust, but it is instructive:
#!/usr/bin/env python
from __future__ import print_function
import os, sys
'''Hacky barebones shell.'''
try:
input=raw_input
except NameError:
pass
def main():
while True:
cmd = input('prompt> ')
args = cmd.split()
if not args:
...
String formatting in Python 3
...format(goals=2, penalties=4)
"({goals} goals, ${penalties})".format(**self.__dict__)
"first goal: {0.goal_list[0]}".format(self)
"second goal: {.goal_list[1]}".format(self)
"conversion rate: {:.2f}".format(self.goals / self.shots) # '0.20'
"conversion rate: {:.2%}".format(self.goals / self.shots) ...