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When to use Cast() and Oftype() in Linq
....OfType<string>(). The reason is that null values are always skipped by .OfType<TResult>(). An example: new System.Collections.ArrayList { "abc", "def", null, "ghi", }.OfType<string>().Count() will give only 3; the similar expression with .Cast<string>() evaluates to 4.
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iphone ios running in separate thread
...so, make sure you aren't diving into concurrency too quickly. Try starting by writing things single-threaded and profile to see if you need to go multithreaded, or if you can design your single-threaded code to be more efficient on its own. For simple tasks, you can sometimes do everything you need ...
how to use XPath with XDocument?
... "Name" nodes under other nodes (which aren't there now but could be added by later changes to the format of the file). However your solution is surely the right one.
– Marco Mp
Feb 21 '13 at 14:12
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git-svn: how do I create a new svn branch via git?
...rameter) auth_bug
Test that your local branch works on that remote branch by using dcommit with --dry-run (-n):
git svn dcommit -n
And SVN server should reply with the new branch name:
Committing to https://scm-server.com/svn/portal/branches/auth_bug ...
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What does 'useLegacyV2RuntimeActivationPolicy' do in the .NET 4 config?
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After a bit of time (and more searching), I found this blog entry by Jomo Fisher.
One of the recent problems we’ve seen is that, because of the support for side-by-side runtimes, .NET 4.0 has changed the way that it binds to older mixed-mode assemblies. These assemblies are, for example,...
Does Redis persist data?
...asically you lose the guaranteed persistence when you increase performance by using only in-memory storing. Imagine a scenario where you INSERT into memory, but before it gets persisted to disk lose power. There will be data loss.
Redis supports so-called "snapshots". This means that it will do a c...
git-checkout older revision of a file under a new name
..., e.g. HEAD:README, :README, master:./README
A suffix : followed by a path names the blob or tree at the given path in the tree-ish object named by the part before the colon. :path (with an empty part before the colon) is a special case of the syntax described next: content recorded in the...
delete map[key] in go?
... the old language, to delete the entry with key k from the map represented by m, one wrote the statement,
m[k] = value, false
This syntax was a peculiar special case, the only two-to-one assignment. It required passing a value (usually ignored) that is evaluated but discarded, plus a boolean that...
Shallow copy of a Map in Java
... [...] It's a shame that Cloneable is broken, but it happens.
Bloch (who by the way, designed and implemented the Collection framework) even went further in saying that he only provides the clone() method just "because people expect it". He does NOT actually recommend using it at all.
I think t...
Change x axes scale in matplotlib
...displayed using the flags in rcParams (from matplotlib import rcParams) or by setting them directly. I haven't found a more elegant way of changing between '1e' and 'x10^' scientific notation than:
ax.xaxis.major.formatter._useMathText = True
This should give you the more Matlab-esc, and indeed a...