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How can I use Homebrew to install both Python 2 and 3 on Mac?
... to switch back and forth between Python 2 and 3. How do I do that using Homebrew as I don't want to mess with path and get into trouble.
Right now I have 2.7 installed through Homebrew.
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Creating rounded corners using CSS [closed]
...he border-radius property. You can read the spec on the property, or get some useful implementation information on MDN:
If you are using a browser that doesn't implement border-radius (Chrome pre-v4, Firefox pre-v4, IE8, Opera pre-v10.5, Safari pre-v5), then the links below detail a whole bunch of ...
How do you detect where two line segments intersect? [closed]
... approach to this problem that uses vector cross products. Define the 2-dimensional vector cross product v × w to be vx wy − vy wx.
Suppose the two line segments run from p to p + r and from q to q + s. Then any point on the first line is representable as p + t r (for a scalar par...
Oracle “Partition By” Keyword
Can someone please explain what the partition by keyword does and give a simple example of it in action, as well as why one would want to use it? I have a SQL query written by someone else and I'm trying to figure out what it does.
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How to check if running as root in a bash script
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The $EUID environment variable holds the current user's UID. Root's UID is 0. Use something like this in your script:
if [ "$EUID" -ne 0 ]
then echo "Please run as root"
exit
fi
Note: If you get 2: [: Illegal number: check if you have ...
What do I have to do to get Core Data to automatically migrate models?
I have read the documentation about automatic /lightweight migration for Core Data models - but I am having problems implementing it.
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Testing web application on Mac/Safari when I don't own a Mac
...ecently when a web site I launched displayed perfectly on IE, Firefox, Chrome and Safari on Windows but was corrupted when viewed using Safari on the Mac (by a potential customer), I need to start testing how my sites look when viewed on a Mac.
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LINQ: Select an object and change some properties without creating a new object
I want to change some properties of a LINQ query result object without creating a new object and manually setting every property. Is this possible?
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Java 8: Where is TriFunction (and kin) in java.util.function? Or what is the alternative?
...ions, destructive and constructive.
While constructive function, as the name implies, constructs something, a destructive one destroys something, but not in the way you may think now.
For example, the function
Function<Integer,Integer> f = (x,y) -> x + y
is a constructive one.
As y...
How to determine if a record is just created or updated in after_save
...hanged? (since it won't change on update) or even created_at_changed? if timestamp columns are present.
Update: As @mitsy points out, if this check is needed outside of callbacks then use id_previously_changed?. See docs.
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