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Is there a command to refresh environment variables from the command prompt in Windows?
...
:SetFromReg
"%WinDir%\System32\Reg" QUERY "%~1" /v "%~2" > "%TEMP%\_envset.tmp" 2>NUL
for /f "usebackq skip=2 tokens=2,*" %%A IN ("%TEMP%\_envset.tmp") do (
echo/set %~3=%%B
)
goto :EOF
:: Get a list of environment variables from registry
:GetRegEnv
"%WinDir%\Syst...
Reference: What is variable scope, which variables are accessible from where and what are “undefined
...
@Arthur There is so much to unpack there… ಠ_ಠ This is most certainly not an approach I would endorse.
– deceze♦
Aug 3 '17 at 8:24
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In where shall I use isset() and !empty()
.....) contains some non-empty data.
To answer question 1 :
$str = '';
var_dump(isset($str));
gives
boolean true
Because the variable $str exists.
And question 2 :
You should use isset to determine whether a variable exists ; for instance, if you are getting some data as an array, you migh...
How to detect if a script is being sourced
...
This seems to be portable between Bash and Korn:
[[ $_ != $0 ]] && echo "Script is being sourced" || echo "Script is a subshell"
A line similar to this or an assignment like pathname="$_" (with a later test and action) must be on the first line of the script or on the...
Stripping everything but alphanumeric chars from a string in Python
...ng.printable (part of the built-in string module). The use of compiled '[\W_]+' and pattern.sub('', str) was found to be fastest.
$ python -m timeit -s \
"import string" \
"''.join(ch for ch in string.printable if ch.isalnum())"
10000 loops, best of 3: 57.6 usec per loop
$ python -m tim...
Converting a Java collection into a Scala collection
... but you can also avoid using jcl.Buffer:
Set(javaApi.query(...).toArray: _*)
Note that scala.collection.immutable.Set is made available by default thanks to Predef.scala.
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How to replace multiple strings in a file using PowerShell
... PowerShell to continue parsing the expression on the next line:
$original_file = 'path\filename.abc'
$destination_file = 'path\filename.abc.new'
(Get-Content $original_file) | Foreach-Object {
$_ -replace 'something1', 'something1aa' `
-replace 'something2', 'something2bb' `
-re...
Rails: around_* callbacks
...classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
...
How to read and write INI file with Python3?
...['DEFAULT']['path'] = '/var/shared/' # update
config['DEFAULT']['default_message'] = 'Hey! help me!!' # create
with open('FILE.INI', 'w') as configfile: # save
config.write(configfile)
You can find more at the official configparser documentation.
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Installing python module within code
...upported by pip. Furthermore since pip v10, all code has been moved to pip._internal precisely in order to make it clear to users that programmatic use of pip is not allowed.
Use sys.executable to ensure that you will call the same pip associated with the current runtime.
import subprocess
import ...