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Postgres: INSERT if does not exist already
...n the updated area at the bottom) including some links if you want to read more about the details.
– Skyguard
Apr 1 '17 at 16:03
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How to get first element in a list of tuples?
...have no order.
Here I've created a flat list because generally that seems more useful than creating a list of 1 element tuples. However, you can easily create a list of 1 element tuples by just replacing seq[0] with (seq[0],).
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Can constructors be async?
... it seems to me that having the possibility of an async constructor brings more trouble than it's worth.
If you actually want the “fire and forget” semantics of async void methods (which should be avoided, if possible), you can easily encapsulate all the code in an async void method and call th...
Is there a Max function in SQL Server that takes two values like Math.Max in .NET?
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Git: Show all of the various changes to a single line in a specified file over the entire git histor
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Since git 1.8.4, there is a more direct way to answer your question.
Assuming that line 110 is the line saying var identifier = "SOME_IDENTIFIER";, then do this:
git log -L110,110:/lib/client.js
This will return every commit which touched that line ...
node.js global variables?
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Could you provide a little bit more information please? Is this part of javascript or part of node? Is it a good pattern to follow? As in should I do this or should I use express set? Thanks
– Harry
Mar 28 '11 at 3:34...
Why use make over a shell script?
...nd on that. While you could do this with a shell script, it would be a lot more work (explicitly checking the last-modified dates on all the files, etc.) The only obvious alternative with a shell script is to rebuild everything every time. For tiny projects this is a perfectly reasonable approach, b...
Is Chrome's JavaScript console lazy about evaluating arrays?
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What are the differences among grep, awk & sed? [duplicate]
...they have the ability to remove, add and modify the text as well (and much more).
awk is mostly used for data extraction and reporting. sed is a stream editor
Each one of them has its own functionality and specialties.
Example
Sed
$ sed -i 's/cat/dog/' file.txt
# this will replace any occurren...
Are trailing commas in arrays and objects part of the spec?
...ertyNameAndValueList }
For arrays literals (Section 11.1.4) it is even more interesting (Update: this already existed in ES3):
ArrayLiteral :
[ Elisionopt ]
[ ElementList ]
[ ElementList , Elision_opt ]
(where Elision_opt is Elisionopt, meaning the Elision is optional)
Elision is...