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Are non-synchronised static methods thread safe if they don't modify static class variables?
... case) are also thread-safe because once created they can't be changed and all threads see the same value. On the other hand if the method was accepting (mutable) Date you could have had a problem. Two threads can simultaneously modify that same object instance, causing race conditions and visibilit...
Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
...ere’s a hint:
h[42] #=> ["a", "b"]
The array returned by each [] call is just the default value, which we’ve been mutating all this time so now contains our new values. Since << doesn’t assign to the hash (there can never be assignment in Ruby without an = present†), we’ve nev...
Comparison of Lucene Analyzers
...text. For example, KeywordAnalyzer you mentioned doesn't split the text at all and takes all the field as a single token. At the same time, StandardAnalyzer (and most other analyzers) use spaces and punctuation as a split points. For example, for phrase "I am very happy" it will produce list ["i", "...
Is it possible to include a file in your .gitconfig
...
actually you don't need ~. this is because your .gitconfig-file still has to reside in ~/.gitconfig a relative path in the config would imply ~...
– robustus
Jul 18 '12 at 15:58
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How do I put a bunch of uncommitted changes aside while working on something else
...y so the branch can continue. It doesn't create a change-set.
hg shelve --all --name "UnfinishedChanges"
hg unshelve --name "UnfinishedChanges"
Update/Edit: Newer versions of mercurial may need to use
hg shelve -n "UnfinishedChanges"
hg unshelve "UnfinishedChanges"
You can still use --name as...
How do I check if a type provides a parameterless constructor?
...Type.EmptyTypes, null);
There's a caveat for value types, which aren't allowed to have a default constructor. You can check if you have a value type using the Type.IsValueType property, and create instances using Activator.CreateInstance(Type);
...
How to delete multiple files at once in Bash on Linux?
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Bash supports all sorts of wildcards and expansions.
Your exact case would be handled by brace expansion, like so:
$ rm -rf abc.log.2012-03-{14,27,28}
The above would expand to a single command with all three arguments, and be equivale...
SQL Server Management Studio won't let me add an index to a table
... "New Index" menu item is grayed out. I don't understand why. I've deleted all data in the table just in case, and refreshed and restarted SSMS, but no luck. I'm using SQL Server 2012 Business Intelligence SP1 CTP.
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Is there any way to redraw tmux window when switching smaller monitor to bigger one?
...Terminal.app. When you "tmux attach" with bigger resolution monitor from smaller one you previously started tmux, it draws dots around the console. It doesn't fit the new window size. Is there any way to redraw and clean the window? CTRL + L or CTRL - B + R doesn't help. I couldn't find any pr...
Aligning text and image on UIButton with imageEdgeInsets and titleEdgeInsets
... image and the start of text. The control itself is Center aligned horizontally (set through Interface Builder)
13 Answers
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