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MySQL CONCAT returns NULL if any field contain NULL
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For those wonder, as I did, what the COALESCE function does: it returns the first non-NULL value parameter passed to it (or NULL if all parameters are NULL). By passing an empty string as the second parameter, you are guaranteeing it will not return...
Homebrew: List only installed top level formulas
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$ brew deps --installed
tmux: pkg-config libevent
q:
gdbm:
libxml2:
asciidoc: docbook
libevent:
pkg-config:
pcre:
docbook:
zsh: gdbm pcre
readline:
emacs: pkg-config
This seems to give us a list of all installed formulae including their dependencies. We can build a list of all formulae and a li...
How do I cast a variable in Scala?
...phics2D] method, but with greater flexibility. For example, you could provide different branches for various types, effectively performing multiple conditional casts at the same time. Finally, you don't really need to throw an exception in the catch-all area, you could also return null (or prefera...
The role of #ifdef and #ifndef
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Text inside an ifdef/endif or ifndef/endif pair will be left in or removed by the pre-processor depending on the condition. ifdef means "if the following is defined" while ifndef means "if the following is not defined".
So:
#define...
How do Google+ +1 widgets break out of their iframe?
Somehow, hovering over a Google+ plus-one widget can introduce a tooltip-type deal that is clearly larger than the <iframe> element in which it is contained. I’ve inspected the DOM to confirm this.*
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How does Apple find dates, times and addresses in emails?
...next word is in "twelfth", any_number ...
then is date
Here is a decent video by a Google engineer on the subject
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How do you use window.postMessage across domains?
... var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled...
Difference between . and : in Lua
...kind of call will be used internally to make sure object and any possible side-effects of calculations/access are calculated only once. Calling object:method(arg1, arg2) is otherwise same as object.method(object, arg1, arg2).
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Android studio: why are minSdkVersion and targetSdkVersion specified both in AndroidManifest.xml and
I just discovered something weird about Android studio: it has some configuration options in the build.gradle file that override what is specified in the AndroidManifest.xml file.
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Python: Get the first character of the first string in a list?
..., subsetting, indexing, then numpy's enhanced fancy indexing".
These two videos cleared things up for me:
"Losing your Loops, Fast Numerical Computing with NumPy" by PyCon 2015:
https://youtu.be/EEUXKG97YRw?t=22m22s
"NumPy Beginner | SciPy 2016 Tutorial" by Alexandre Chabot LeClerc:
https://youtu...