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Check existence of input argument in a Bash shell script
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I like to do it this way, in terse syntax and still POSIX acceptable. [ -z "$1" ] && echo "No argument supplied" I prefer one-liners, as they are easier for me; and it's also faster to check exit value, compared to using if
– J. M. Beck...
Hidden features of Python [closed]
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In case you're thinking it's doing 1 < x, which comes out as True, and then comparing True < 10, which is also True, then no, that's really not what happens (see the last example.) It's really translating into 1 < x and x < 10, and x < 10 and 10 < x * 10 and x*10 < 100, but...
How to use sed to replace only the first occurrence in a file?
...r if you prefer' solution. It would also be good to explain the answers - and to make the answer address the question directly, and then generalize, rather than generalize only. But good answer.
– Jonathan Leffler
Sep 29 '08 at 13:15
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What is the difference between '@' and '=' in directive scope in AngularJS?
I've read the AngularJS documentation on the topic carefully, and then fiddled around with a directive. Here's the fiddle .
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Understanding ibeacon distancing
...estimates.
While the distance estimates are useful, they are not perfect, and require that you control for other variables. Be sure you read up on the complexities and limitations before misusing this.
When we were building the Android iBeacon library, we had to come up with our own independent a...
Android Studio Stuck at Gradle Download on create new project
I have installed the new Android Studio . Everything was working fine but when I try to create a new project it gets stuck at downloading Gradle .
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Understanding dict.copy() - shallow or deep?
... 3, 4, 5]}, {1: [1, 2, 3, 4]})
So:
b = a: Reference assignment, Make a and b points to the same object.
b = a.copy(): Shallow copying, a and b will become two isolated objects, but their contents still share the same reference
b = copy.deepcopy(a): Deep copying, a and b's structure and conte...
What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?
I am transitioning from Java to C++ and have some questions about the long data type. In Java, to hold an integer greater than 2 32 , you would simply write long x; . However, in C++, it seems that long is both a data type and a modifier.
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How to enable MySQL Query Log?
...he MySQL function that logs each SQL query statement received from clients and the time that query statement has submitted?
Can I do that in phpmyadmin or NaviCat?
How do I analyse the log?
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What is the difference between range and xrange functions in Python 2.X?
Apparently xrange is faster but I have no idea why it's faster (and no proof besides the anecdotal so far that it is faster) or what besides that is different about
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