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Can I export a variable to the environment from a bash script without sourcing it?
... is to source the variable:
. ./export.bash
or
source ./export.bash
Now when echoing from main shell it works
echo $VAR
HELLO, VARABLE
We will now reset VAR
export VAR=""
echo $VAR
Now we will execute a script to source the variable then unset it :
./test-export.sh
HELLO, VARABLE
--
...
How can I check for “undefined” in JavaScript? [duplicate]
...n window; // true
"theFoo" in window; // false
If you are interested in knowing whether the variable hasn't been declared or has the value undefined, then use the typeof operator, which is guaranteed to return a string:
if (typeof myVar !== 'undefined')
Direct comparisons against undefined are ...
What is this Javascript “require”?
...b browser with a limited global context defined mostly by what came to be known as the Document Object Model (DOM) level 0 (the Netscape Navigator Javascript API).
Server-side Javascript eliminates that restriction and allows Javascript to call into various pieces of native code (like the Postgres ...
What Are Some Good .NET Profilers?
...st few years, and its memory profiler has some truly useful features which now pushed it ahead of dotTrace as a package in my estimation. I'm lucky enough to have licenses for both, but if you are going to buy one .Net profiler for both performance and memory, make it ANTS.
...
Django development IDE [closed]
...ans starting to get Python support, but I have no idea where that is right now. Lots of people rave about NetBeans 6, but in the Java world Eclipse still reigns as the king of the OSS IDEs.
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Can C++ code be valid in both C++03 and C++11 but do different things?
...e plus side there is:
Code that previously implicitly copied objects will now implicitly move them when possible.
On the negative side, several examples are listed in the appendix C of the standard. Even though there are many more negative ones than positive, each one of them is much less likely t...
Can IntelliJ IDEA encapsulate all of the functionality of WebStorm and PHPStorm through plugins? [cl
...gurations that are hooked to iOS Simulator etc.
RubyMine has all of these now, IDEA does not. So I would have to generate a RubyMotion project outside of IDEA, then setup an IDEA project and hook up to that source folder etc and God knows what else.
What JetBrains should do is have a licensing mod...
What is more efficient: Dictionary TryGetValue or ContainsKey+Item?
...
you can actually look at the .net source for it now too: referencesource.microsoft.com/#mscorlib/system/collections/… you can see that all 3 of TryGetValue, ContainsKey, and this[] call the same FindEntry method and do the same amount of work, only differing in how they...
How to get the day of week and the month of the year?
I don't know much about Javascript, and the other questions I found are related to operations on dates, not only getting the information as I need it.
...
mongodb: insert if not exists
... specify what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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