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Programmatically access currency exchange rates [closed]
...S dollars or Euros so they don't have to make the mental effort to convert from Australian dollars.
15 Answers
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How to upgrade PostgreSQL from version 9.6 to version 10.1 without losing data?
...s10.1 -E utf8
run pg_upgrade (note: change bin version if you're upgrading from something other than below):
pg_upgrade -v \
-d /usr/local/var/postgres \
-D /usr/local/var/postgres10.1 \
-b /usr/local/Cellar/postgresql/9.6.5/bin/ \
-B /usr/local/Cellar/postgresql/10.1/bin/
-v to e...
How to manage local vs production settings in Django?
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In settings.py:
try:
from local_settings import *
except ImportError as e:
pass
You can override what needed in local_settings.py; it should stay out of your version control then. But since you mention copying I'm guessing you use none ;)
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Design Patterns: Abstract Factory vs Factory Method
...omplicated refer to next diagram for better real-life example).
Example From The .NET Framework
DbFactoriesProvider is a Simple Factory as it has no sub-types. The DbFactoryProvider is an abstract factory as it can create various related database objects such as connection and command objects.
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How to send email from Terminal?
I know there are ways to send email from terminal in Linux/MacOS, but I can't seem to find proper documentation on how to do that.
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How to break/exit from a each() function in JQuery? [duplicate]
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"simple return" actually returns. It will return control from the each and everything else around it and after it until it exit's each()'s parent control - such as a function() which is using each. This is the correct answer, and the other approach will not work.
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What does FETCH_HEAD in Git mean?
...TCH_HEAD is a short-lived ref, to keep track of what has just been fetched from the remote repository. git pull first invokes git fetch, in normal cases fetching a branch from the remote; FETCH_HEAD points to the tip of this branch (it stores the SHA1 of the commit, just as branches do). git pull th...
What's the difference between a proc and a lambda in Ruby?
...mbda {} gives you a proc that checks the number of arguments passed to it. From ri Kernel#lambda:
Equivalent to Proc.new, except the resulting Proc objects check the number of parameters passed when called.
An example:
p = Proc.new {|a, b| puts a**2+b**2 } # => #<Proc:0x3c7d28@(irb):1&g...
Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...re work for the scheduler.
One thread for all connections.
This takes load from the system because we have fewer threads. But it also prevents you from using the full performance of your machine, because you might end up driving one processor to 100% and letting all other processors idle around.
A f...
What is 'Context' on Android?
...xt(), getContext(), getBaseContext() or this (when in a class that extends from Context, such as the Application, Activity, Service and IntentService classes).
Typical uses of context:
Creating new objects:
Creating new views, adapters, listeners:
TextView tv = new TextView(getContext());
ListAd...