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How do I know which version of Javascript I'm using?
I'm just reading this documentation about Javascript 1.2, but I'm wondering which version of Javascript is being used in the most popular browsers.
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MySQL high CPU usage [closed]
...se MySQL to eat up CPU.
You'll also probably want to give the following a read over as they contain some good information.
How MySQL Uses Memory
MySQL System Variables
It's also a very good idea to use a profiler. Something you can turn on when you want that will show you what queries your appl...
Android: java.lang.SecurityException: Permission Denial: start Intent
...T_COMPLETED"/> <uses-permission android:name="android.permission.READ_CONTACTS"/> <uses-permission android:name="android.permission.READ_SYNC_SETTINGS"/> <uses-permission android:name="android.permission.READ_OWNER_DATA"/> <uses-permission android:name="androi...
What happens to a declared, uninitialized variable in C? Does it have a value?
... // also zero
}
Non-static variables (local variables) are indeterminate. Reading them prior to assigning a value results in undefined behavior.
void foo() {
int x;
printf("%d", x); // the compiler is free to crash here
}
In practice, they tend to just have some nonsensical value in there ...
How can I extract a predetermined range of lines from a text file on Unix?
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You don't need the cat command; head can read a file directly. This is slower than many alternatives because it uses 2 (3 as shown) commands where 1 is sufficient.
– Jonathan Leffler
Jan 5 '15 at 18:41
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Why is React's concept of Virtual DOM said to be more performant than dirty model checking?
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I recently read a detailed article about React's diff algorithm here: http://calendar.perfplanet.com/2013/diff/. From what I understand, what makes React fast is:
Batched DOM read/write operations.
Efficient update of sub-tree only.
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What's the u prefix in a Python string?
...ead simplest, probably flawed, solution this second.
A: You should really read Joel's Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!) essay on character sets.
Q: sry no time code pls
A: Fine. try str('Some String') or 'Some...
PostgreSQL ERROR: canceling statement due to conflict with recovery
...be canceled more often.
You can work around this by starting a repeatable read transaction on primary which does a dummy query and then sits idle while a real query is run on secondary. Its presence will prevent vacuuming of old row versions on primary.
More on this subject and other workarounds a...
What is a MIME type?
I have been reading about how to build plug-ins and this "MIME type" keeps getting discussed in it. I have tried to look into it and know that it is Multipurpose Internet Mail Extensions (MIME) but no suitable explanation of how it relates to browser plug-ins, as in what I need to know about it for ...
How can I use inverse or negative wildcards when pattern matching in a unix/linux shell?
...@MarkStosberg. Although, one fringe benefit of this technique is you could read exclusions from an actual file, e.g. comm -23 <(ls) exclude_these.list
– James M. Lay
Dec 5 '17 at 18:10
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