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How to get the unix timestamp in C#
...mestamp:
DateTimeOffset.UtcNow.ToUnixTimeSeconds()
To get the timestamp from a DateTime:
DateTime foo = DateTime.UtcNow;
long unixTime = ((DateTimeOffset)foo).ToUnixTimeSeconds();
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impro...
Elegant way to check for missing packages and install them?
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Yes. If you have your list of packages, compare it to the output from installed.packages()[,"Package"] and install the missing packages. Something like this:
list.of.packages <- c("ggplot2", "Rcpp")
new.packages <- list.of.packages[!(list.of.packages %in% installed.packages()[,"Pac...
How do I update each dependency in package.json to the latest version?
I copied package.json from another project and now want to bump all of the dependencies to their latest versions since this is a fresh project and I don't mind fixing something if it breaks.
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How can I scale an image in a CSS sprite
...ricks.com/css-sprites/ , it talks about how can I crop off a smaller image from 1 bigger image. Can you please tell me if it is possible/how I can crop off a smaller image and then scale the cropped off region before I lay it out?
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What are enums and why are they useful?
...ers (or String codes), you increase compile-time checking and avoid errors from passing in invalid constants, and you document which values are legal to use.
BTW, overuse of enums might mean that your methods do too much (it's often better to have several separate methods, rather than one method th...
What's the difference between istringstream, ostringstream and stringstream? / Why not use stringstr
...t of the same string stream.
Usually I want to either initialize a stream from a string and then parse it; or stream things to a string stream and then extract the result and store it.
If you're streaming to and from the same stream, you have to be very careful with the stream state and stream pos...
Reference: Comparing PHP's print and echo
...non-zero values (positive and negative) are truthy values and this derives from PHP's Perl legacy.
But, if this is the case, then one may wonder why echo take multiple arguments whereas print can only handle one. For this answer we need to turn to the parser, specifically the file zend_language_...
What are “first class” objects?
...st class" in a given programming language, and why? In what do they differ from languages where they are not?
5 Answers
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What's an object file in C?
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An object file is the real output from the compilation phase. It's mostly machine code, but has info that allows a linker to see what symbols are in it as well as symbols it requires in order to work. (For reference, "symbols" are basically names of global ...
How do I get bash completion to work with aliases?
...lly figured out how to do this properly! Step 1) Copy git-completion.bash from <your git install folder>/etc/bash-completion.d/ to ~/.git-completion.bash Step 2) add source ~/.git-completion.bash to your .bash_profile Step 3) Add __git_complete gco _git_checkout anywhere after the above lin...