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Is recursion ever faster than looping?
...n some environments these functions are the first (or only) to get a boost from automatic parallelization — so they can be significantly faster than either iteration or recursion. Data Parallel Haskell is an example of such an environment.
List comprehensions are another alternative, but these ...
Type of conditional expression cannot be determined because there is no implicit conversion between
...has type X and y has type Y then
If an implicit conversion (§6.1) exists from X to Y, but not from Y to X, then Y is the type of the conditional expression.
If an implicit conversion (§6.1) exists from Y to X, but not from X to Y, then X is the type of the conditional expression.
Otherwise, no ...
Basic http file downloading and saving to disk in python?
...trieve("http://randomsite.com/file.gz", "file.gz")
This downloads a file from a website and names it file.gz. This is one of my favorite solutions, from Downloading a picture via urllib and python.
This example uses the urllib library, and it will directly retrieve the file form a source.
...
How do you run a crontab in Cygwin on Windows?
...ndows Scheduler, but others don't have an .exe extension so can't be run from DOS (it seems like).
8 Answers
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403 Forbidden vs 401 Unauthorized HTTP responses
...
A clear explanation from Daniel Irvine:
There's a problem with 401 Unauthorized, the HTTP status code for authentication errors. And that’s just it: it’s for authentication, not authorization.
Receiving a 401 response is the server tel...
Capturing Groups From a Grep RegEx
...pace. It's awkward to escape and you can't use quotes since that forces it from a regex to an ordinary string. The correct way to do it is to use a variable. Quotes can be used during the assignment making things much simpler.
– Paused until further notice.
Oct...
Checking for a null int value from a Java ResultSet
In Java I'm trying to test for a null value, from a ResultSet, where the column is being cast to a primitive int type.
1...
No module named _sqlite3
...
I had the same problem (building python2.5 from source on Ubuntu Lucid), and import sqlite3 threw this same exception. I've installed libsqlite3-dev from the package manager, recompiled python2.5, and then the import worked.
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Maven dependency for Servlet 3.0 API?
...s. Is there a source that confirms this assumption?
The maven repository from Java.net indeed offers the following artifact for the WebProfile:
<repositories>
<repository>
<id>java.net2</id>
<name>Repository hosting the jee6 artifacts</name>
<u...
How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?
...ng gemsets:
$ rvm upgrade 1.9.2-p0 1.9.2
Are you sure you wish to upgrade from ruby-1.9.2-p0 to ruby-1.9.2-p136? (Y/n): Y
To replace with the latest stable release of 1.9.2. This avoids clutter.
Some additional helpful tips, thanks to comments (@Mauro, @James, @ACB)
$ rvm list known
# NOTE: yo...