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How to check if multiple array keys exists
...o check (like in the original question), it's probably easy enough to just call array_key_exists() twice to check if the keys exists.
if (array_key_exists("story", $arr) && array_key_exists("message", $arr)) {
// Both keys exist.
}
However this obviously doesn't scale up well to many ...
Swift: Testing optionals for nil
... let
guard let can do similar things. It's main purpose is to make it logically more reasonable. It's like saying Make sure the variable is not nil, otherwise stop the function. guard let can also do extra condition checking as if let.
The differences are that the unwrapped value will be available...
How to compare files from two different branches?
...ppens. I have my difftool configured (it works for merging). I have a file called bd.ps1. Every version of the command I type does nothing. Doesn't even give an errer. WTH!?!?!
– Micah
Nov 4 '10 at 18:46
...
Order Bars in ggplot2 bar graph
...order. If left unspecified, the levels of a factor will be sorted alphabetically. You can also specify the level order within the call to factor as above, and other ways are possible as well.
theTable$Position <- factor(theTable$Position, levels = c(...))
...
How do I rename a local Git branch?
...is --move, e.g., git branch --move master renames the current branch to be called "master".
– robenkleene
Sep 22 '15 at 17:56
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show 11 more...
how to convert from int to char*?
... @Griwes: the question is how to get to char*, not "is there any point calling from C++ into existing libraries written in C, or should I re-implement them in C++?" ;-p
– Steve Jessop
Jun 3 '12 at 9:57
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How to correctly close a feature branch in Mercurial?
...esults back to the default branch and close feature-x in order to get rid of it in the output of hg branches .
4 Answe...
rsync: difference between --size-only and --ignore-times
...cription: https://www.andrew.cmu.edu/course/15-749/READINGS/required/cas/tridgell96.pdf. The wikipedia article on rsync is also very good.
For local files, rsync compares metadata and if it looks like it doesn't need to copy the file because size and timestamp match between source and destination i...
Best way to require all files from a directory in ruby?
... According to the Pickaxe, the .rb extension is optional. Technically it changes the meaning: "require 'foo.rb'" requires foo.rb, whereas "require 'foo'" might require foo.rb, foo.so or foo.dll.
– Sam Stokes
Apr 9 '09 at 17:46
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Set transparent background using ImageMagick and commandline prompt
....
bg_removal script
By the way, ImageMagick actually comes with a script called
"bg_removal"
which uses floodfill in a similar manner as my solution. However, the
results are not great because it still uses 1-bit alpha. Also, the
bg_removal script runs slower and is a little bit trickier to use (i...