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Test if a variable is a list or tuple
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Go ahead and use isinstance if you need it. It is somewhat evil, as it excludes custom sequences, iterators, and other things that you might actually need. However, sometimes you need to behave differently if someone, for instance, ...
Check if a value is an object in JavaScript
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UPDATE:
This answer is incomplete and gives misleading results. For example, null is also considered of type object in JavaScript, not to mention several other edge cases. Follow the recommendation below and move on to other "most upvoted (and correct!) answe...
How to debug Lock wait timeout exceeded on MySQL?
...nnoDB tables.
Since you know the query, all the tables being accessed are candidates for being the culprit.
From there, you should be able to run SHOW ENGINE INNODB STATUS\G
You should be able to see the affected table(s)
You get all kinds of additional Locking and Mutex Information.
Here is a sampl...
Why can't I stop vim from wrapping my code?
...idth' is zero, 'wrapmargin' may be used. See also
'formatoptions' and |ins-textwidth|.
When 'formatexpr' is set it will be used to break the line.
NOTE: This option is set to 0 when 'compatible' is set.
'wrapmargin' 'wm' number (default 0)
l...
What do linkers do?
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To understand linkers, it helps to first understand what happens "under the hood" when you convert a source file (such as a C or C++ file) into an executable file (an executable file is a file that can be executed on your machine or so...
What are the differences between vector and list data types in R?
What are the main differences between vector and list data types in R? What are the advantages or disadvantages of using (or not) these two data types?
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Inline SVG in CSS
...rk nicely is Safari (5.1.4). In Opera 11.62 the gradient is black, in IE 9 and Firefox 12 it's white. In Chrome 19, it works UNLESS you specify the width/height of the SVG in % units. I'd say it's more of an oddity than a real feature. It's a cool find though.
– toniedzwiedz
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What is the best way to give a C# auto-property an initial value?
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In C# 5 and earlier, to give auto implemented properties an initial value, you have to do it in a constructor.
Since C# 6.0, you can specify initial value in-line. The syntax is:
public int X { get; set; } = x; // C# 6 or higher
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Pointers, smart pointers or shared pointers? [duplicate]
...ting/copying/destructing a shared pointer needs to be an atomic operation, and this can hinder performance if you have many threads running. However, it won't always be the case - only testing will tell you for sure.
There is an argument (that I like) against shared pointers - by using them, you ar...
List Git aliases
... list of my git aliases, i.e., something analogous to the bash alias command?
16 Answers
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