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How to specialize std::hash::operator() for user-defined type in unordered containers?
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edited Nov 16 '11 at 20:14
answered Nov 16 '11 at 20:07
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Inno Setup for Windows service?
... Stocker
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answered Sep 20 '09 at 1:39
lubos haskolubos hasko
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How to get the original value of an attribute in Rails
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Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should append _before_last_save
Something like:
before_save object
do_something_with object.name_before_last_save
end
Will return the name value bef...
Ways to iterate over a list in Java
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edited Jan 30 at 15:22
Olivier
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answered Aug 23 '13 at 19:29
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How to change the font size on a matplotlib plot
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craymichael
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answered Oct 10 '10 at 11:49
Herman SchaafHerman Schaaf
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What events does an fire when it's value is changed?
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alex
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answered Oct 15 '10 at 7:30
Jacob Relkin...
How did this person code “Hello World” with Microsoft Paint?
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answered Apr 7 '11 at 23:08
Andrew GrimmAndrew Grimm
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Why is Cache-Control attribute sent in request header (client to server)?
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140
Cache-Control: no-cache is generally used in a request header (sent from web browser to server) ...
scopes with lambda and arguments in Rails 4 style?
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307
I think it should be:
scope :find_lazy, -> (id) { where(id: id) }
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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
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(For information about the new exception helper in Visual Studio 2017 see the end of this answer)
Consider this code:
String s = null;
Console.WriteLine(s.Length);
This will throw a NullReferenceException in the second line and you want to know why .NET doesn't tell you that it was s ...