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Using do block vs braces {}
... is a bit old question but I would like to try explain a bit more about {} and do .. end
like it is said before
bracket syntax has higher precedence order than do..end
but how this one makes difference:
method1 method2 do
puts "hi"
end
in this case, method1 will be called with the bloc...
Synchronously waiting for an async operation, and why does Wait() freeze the program here
...ing on a thread pool thread, it doesn't try to come back to the UI thread, and everything therefore works.
Alternatively, you could call StartAsTask().ConfigureAwait(false) before awaiting the inner operation to make it come back to the thread pool rather than the UI thread, avoiding the deadlock e...
How to select unique records by SQL
...
With the distinct keyword with single and multiple column names, you get distinct records:
SELECT DISTINCT column 1, column 2, ...
FROM table_name;
share
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imp...
Is String.Format as efficient as StringBuilder
...would run more quickly using .Append(). But it's a guess, try benchmarking and/or profiling the two to get a proper comparison.
This chap, Jerry Dixon, did some benchmarking:
http://jdixon.dotnetdevelopersjournal.com/string_concatenation_stringbuilder_and_stringformat.htm
Updated:
Sadly the ...
How to filter Pandas dataframe using 'in' and 'not in' like in SQL
How can I achieve the equivalents of SQL's IN and NOT IN ?
9 Answers
9
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Reading an Excel file in PHP [closed]
...Excel file (Office 2003). There is an Excel file that needs to be uploaded and its contents parsed.
8 Answers
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Error when changing to master branch: my local changes would be overwritten by checkout
...
Your error appears when you have modified a file and the branch that you are switching to has changes for this file too (from latest merge point).
Your options, as I see it, are - commit, and then amend this commit with extra changes (you can modify commits in git, as long...
Logging levels - Logback - rule-of-thumb to assign log levels
..., so my answer is biased towards looking at it from a production support standpoint; that said, we assign roughly as follows:
error: the system is in distress, customers are probably being affected (or will soon be) and the fix probably requires human intervention. The "2AM rule" applies here- if...
What's the difference between :: (double colon) and -> (arrow) in PHP?
...to access instance members).
In general, :: is used for scope resolution, and it may have either a class name, parent, self, or (in PHP 5.3) static to its left. parent refers to the scope of the superclass of the class where it's used; self refers to the scope of the class where it's used; static r...
Rails DB Migration - How To Drop a Table?
...ation to already have the code you want. You can create an empty migration and then populate it with the code you need.
You can find information about how to accomplish different tasks in a migration here:
http://api.rubyonrails.org/classes/ActiveRecord/Migration.html
More specifically, you can s...