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How to tell if a string is not defined in a Bash shell script
... answer you are after is implied (if not stated) by Vinko's answer, though it is not spelled out simply. To distinguish whether VAR is set but empty or not set, you can use:
if [ -z "${VAR+xxx}" ]; then echo VAR is not set at all; fi
if [ -z "$VAR" ] && [ "${VAR+xxx}" = "xxx" ]; then echo V...
Check if table exists without using “select from”
Is there a way to check if a table exists without selecting and checking values from it?
17 Answers
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How to define two angular apps / modules in one page?
... using angular.bootstrap instead. AngularJS applications cannot be nested within each other.
-- http://docs.angularjs.org/api/ng.directive:ngApp
See also
https://groups.google.com/d/msg/angular/lhbrIG5aBX4/4hYnzq2eGZwJ
http://docs.angularjs.org/api/angular.bootstrap
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Detailed 500 error message, ASP + IIS 7.5
...s To Browser" is not working set also this:
Error Pages -> 500 -> Edit Feature Settings -> "Detailed Errors"
Also note that if the content of the error page sent back is quite short and you're using IE, IE will happily ignore the useful content sent back by the server and show you its o...
What is the 'instanceof' operator used for in Java?
...Cat extends Animal implements Domestic {}
Imagine a dog object, created with Object dog = new Dog(), then:
dog instanceof Domestic // true - Dog implements Domestic
dog instanceof Animal // true - Dog extends Animal
dog instanceof Dog // true - Dog is Dog
dog instanceof Object // true - ...
Best way to add Activity to an Android project in Eclipse?
When adding an activity to an existing Android project, I manually create a new class - is that the best / preferred way? How do others handle that?
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Find location of a removable SD card
...on is about external SD. How to get a path like "/mnt/sdcard/external_sd" (it may differ from device to device)?
Android has no concept of "external SD", aside from external storage, as described above.
If a device manufacturer has elected to have external storage be on-board flash and also has an ...
Check if Key Exists in NameValueCollection
... a quick and simple way to check if a key exists in a NameValueCollection without looping through it?
12 Answers
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Most common C# bitwise operations on enums
For the life of me, I can't remember how to set, delete, toggle or test a bit in a bitfield. Either I'm unsure or I mix them up because I rarely need these. So a "bit-cheat-sheet" would be nice to have.
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How to encrypt String in Java
...ch will show up in 2D barcode(PDF-417) so when someone get an idea to scan it will get nothing readable.
16 Answers
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