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Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...or the request and a background thread (async) looping to read a file, database or whatever.
– JavierJ
Nov 30 '15 at 18:22
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How is this fibonacci-function memoized?
...t one.
It's essentially a clever and low-rent form of dynamic programming based on GHC's lazy semantics. I think the standard only specifies that it has to be non-strict, so a compliant compiler could potentially compile this code to not memoize. However, in practice, every reasonable compiler is g...
How to split a delimited string in Ruby and convert it to an array?
... to use the split method in the ruby docs
Divides str into substrings based on a delimiter, returning an array
of these substrings.
If pattern is a String, then its contents are used as the delimiter
when splitting str. If pattern is a single space, str is split on
whitespace, with l...
How do I check if a SQL Server text column is empty?
...ullness and emptiness nature of a text column and accordingly assign value based on condition. Upvote for the answer since this is what I was looking for. Thanks
– user_v
Feb 3 '12 at 17:10
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Rails: Why does find(id) raise an exception in rails? [duplicate]
If there is no user with an id of 1 in the database, trying User.find(1) will raise an exception.
2 Answers
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jQuery: count number of rows in a table
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@DevlshOne That is not true, length is not zero base, check the documentation: api.jquery.com/length
– Miguel
May 1 '13 at 16:01
1
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How to add include path in Qt Creator?
...ur own build system, you create a project by selecting "Import of Makefile-based project". This will create some files in your project directory including a file named <your project name>.includes. In that file, simply list the paths you want to include, one per line. Really all this does i...
What is the meaning of the 'g' flag in regular expressions?
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Will give example based on string. If we want to remove all occurences from a
string.
Lets say if we want to remove all occurences of "o" with "" from "hello world"
"hello world".replace(/o/g,'');
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How to check if a DateTime occurs today?
...s a DateTime object
.NET is smart enough to determine you want to compare based on Date only and uses that for the internal Compare. Not sure why, and actually having trouble finding documentation for this behaviour.
share
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Extract a regular expression match
...nces in 'See also':
‘regmatches’ for extracting matched substrings based on the results of
‘regexpr’, ‘gregexpr’ and ‘regexec’.
So this will work, and is fairly simple:
txt <- "aaa12xxx"
regmatches(txt,regexpr("[0-9]+",txt))
#[1] "12"
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