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Performance difference for control structures 'for' and 'foreach' in C#

...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop. I'd personally use LINQ to avoid the "if" too: foreach (var item in list.Where(condition)) { } EDI...
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Capturing Groups From a Grep RegEx

...egex="[0-9]+_([a-z]+)_[0-9a-z]*" for f in $files # unquoted in order to allow the glob to expand do if [[ $f =~ $regex ]] then name="${BASH_REMATCH[1]}" echo "${name}.jpg" # concatenate strings name="${name}.jpg" # same thing stored in a variable else ...
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List directory tree structure in python?

I know that we can use os.walk() to list all sub-directories or all files in a directory. However, I would like to list the full directory tree content: ...
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How do I override nested NPM dependency versions?

...d my npm-shrinkwrap.json file. Yarn has https://yarnpkg.com/lang/en/docs/selective-version-resolutions/ for this. Neat. Check out this answer too: https://stackoverflow.com/a/41082766/3051080 share | ...
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Get event listeners attached to node using addEventListener

... You can't. The only way to get a list of all event listeners attached to a node is to intercept the listener attachment call. DOM4 addEventListener Says Append an event listener to the associated list of event listeners with type set to type, listener set to ...
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How do I import other TypeScript files?

... You can use the --all flag with tsc on your main .ts file. The compiler figures out all the dependencies based on your reference tags and generates a single output .js file for the entire application: tsc --out app.js main.ts ...
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How to get the body's content of an iframe in Javascript?

...getElementById('id_description_iframe'); // or var iframe = document.querySelector('#id_description_iframe'); And then use jQuery's solution var iframeDocument = iframe.contentDocument || iframe.contentWindow.document; It works even in the Internet Explorer which does this trick during the ...
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How to assign colors to categorical variables in ggplot2 that have stable mapping?

...maintain consistent color schemes across multiple data frames that are not all obtained by subsetting a single large data frame. Managing the factors levels in multiple data frames can become tedious if they are being pulled from separate files and not all factor levels appear in each file. One way...
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String concatenation in Ruby

...ficient in term of memory/speed from what I've seen (not measured though). All three methods will throw an uninitialized constant error when ROOT_DIR is nil. When dealing with pathnames, you may want to use File.join to avoid messing up with pathname separator. In the end, it is a matter of taste....
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“Inner exception” (with traceback) in Python?

...recently started programming in Python. When an exception is thrown I typically want to wrap it in another exception that adds more information, while still showing the full stack trace. It's quite easy in C#, but how do I do it in Python? ...