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How to check if element has any children in Javascript?
... about child elements (as opposed to text nodes, attribute nodes, etc.) on all modern browsers (and IE8 — in fact, even IE6) you can do this: (thank you Florian!)
if (element.children.length > 0) { // Or just `if (element.children.length)`
// It has at least one element as a child
}
Tha...
PostgreSQL: Show tables in PostgreSQL
...terface,
First, choose your database
\c database_name
Then, this shows all tables in the current schema:
\dt
Programmatically (or from the psql interface too, of course):
SELECT * FROM pg_catalog.pg_tables;
The system tables live in the pg_catalog database.
...
How can I search for a multiline pattern in a file?
I needed to find all the files that contained a specific string pattern. The first solution that comes to mind is using find piped with xargs grep :
...
Maximum and Minimum values for ints
...on doesn't apply. The plain int type is unbounded.
However, you might actually be looking for information about the current interpreter's word size, which will be the same as the machine's word size in most cases. That information is still available in Python 3 as sys.maxsize, which is the maximum ...
Why is lazy evaluation useful?
...epending on the sequence of conditional expressions, only a subset may actually be used. In a language like C, all three values would be computed anyway; but in Haskell, only the necessary values are computed.
It also allows for cool stuff like infinite lists. I can't have an infinite list in a lan...
Retrieve filename from file descriptor in C
...fd you have, and make sure st_dev and st_ino are the same.
Of course, not all file descriptors refer to files, and for those you'll see some odd text strings, such as pipe:[1538488]. Since all of the real filenames will be absolute paths, you can determine which these are easily enough. Further, as...
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize
...|
edited Mar 25 '14 at 13:05
answered Mar 25 '14 at 12:30
B...
How do I pass the value (not the reference) of a JS variable to a function? [duplicate]
...selection(i);
});
})(i);
}
By creating an anonymous function and calling it with the variable as the first argument, you're passing-by-value to the function and creating a closure.
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Why is it bad style to `rescue Exception => e` in Ruby?
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TL;DR: Use StandardError instead for general exception catching. When the original exception is re-raised (e.g. when rescuing to log the exception only), rescuing Exception is probably okay.
Exception is the root of Ruby's exception hierarch...
How to get the error message from the error code returned by GetLastError()?
After a Windows API call, how can I get the last error message in a textual form?
11 Answers
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