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Python Infinity - Any caveats?
...involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**2
4294967296.0
>>> _**2
1.84467440737...
How to know if other threads have finished?
...Thread to complete, or
Check Thread.isAlive() in a polling fashion -- generally discouraged -- to wait until each Thread has completed, or
Unorthodox, for each Thread in question, call setUncaughtExceptionHandler to call a method in your object, and program each Thread to throw an uncaught Exception...
Where is the documentation for the values() method of Enum?
...places :
Enum Types, from The Java Tutorials
The compiler automatically adds some special methods when it creates
an enum. For example, they have a static values method that returns an
array containing all of the values of the enum in the order they are
declared. This method is commonl...
Check if a table exists in Rails
...? 'kittens'
In Rails 2, 3 & 4 the API is about tables.
# Listing of all tables and views
ActiveRecord::Base.connection.tables
# Checks for existence of kittens table/view (Kitten model)
ActiveRecord::Base.connection.table_exists? 'kittens'
Getting the status of migrations:
# Tells you all...
What's the fuss about Haskell? [closed]
...eems to love that language. Being good at Haskell seems somewhat like the hallmark of a genius programmer.
17 Answers
...
Why are C# 3.0 object initializer constructor parentheses optional?
It seems that the C# 3.0 object initializer syntax allows one to exclude the open/close pair of parentheses in the constructor when there is a parameterless constructor existing. Example:
...
Best way to create an empty object in JSON with PHP?
To create an empty JSON object I do usually use:
7 Answers
7
...
Easy way to list node modules I have npm linked?
...ts (e.g. ls -l node_modules | grep ^l)? They're normal symlinks.
If you really need to find all symlinks, you could try something like find / -type d -name "node_modules" 2>/dev/null | xargs -I{} find {} -type l -maxdepth 1 | xargs ls -l.
...
Why is Git better than Subversion?
...urceSafe , I just love Subversion. Combined with TortoiseSVN , I can't really imagine how it could be any better.
30 An...
Is there an SQLite equivalent to MySQL's DESCRIBE [table]?
...
You can use ".schema" without a table and it'll show you all of them.
– Dan Benamy
Nov 30 '12 at 6:16
46
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