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Rails - Could not find a JavaScript runtime?
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Installing a javascript runtime library such as nodejs solves this
To install nodejs on ubuntu, you can type the following command in the terminal:
sudo apt-get install nodejs
To install nodejs on systems using yum, type the fol...
Check Whether a User Exists
...t, you got command return value ($?)1
And as other answers pointed out: if all you want is just to check if the user exists, use if with id directly, as if already checks for the exit code. There's no need to fiddle with strings, [, $? or $():
if id "$1" &>/dev/null; then
echo 'user found...
How are msys, msys2, and msysgit related to each other?
...though it does that very well). It has a software building infrastructure called makepkg that allows the creation of recipes (PKGBUILD and patch files) for building software.
IMHO, the adoption of Pacman changes things significantly for open source development on Windows. Instead of everyone hackin...
How to dynamically create generic C# object using reflection? [duplicate]
...create the object, just for the sake or creating it. You probably want to call some method on your newly created instance.
You'll then need something like an interface :
public interface ITask
{
void Process(object o);
}
public class Task<T> : ITask
{
void ITask.Process(object o)
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Automatic exit from bash shell script on error [duplicate]
...u can also disable this behavior with set +e.
You may also want to employ all or some of the the -e -u -x and -o pipefail options like so:
set -euxo pipefail
-e exits on error, -u errors on undefined variables, and -o (for option) pipefail exits on command pipe failures. Some gotchas and workaro...
postgresql - sql - count of `true` values
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You can actually omit ELSE null to get the same result.
– 200_success
May 12 '16 at 18:26
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How to add a delay for a 2 or 3 seconds [closed]
...swered Mar 27 '11 at 14:46
digEmAlldigEmAll
51.9k99 gold badges106106 silver badges131131 bronze badges
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Creating a UIImage from a UIColor to use as a background image for UIButton [duplicate]
...'re trying to apply; the CGColor is backed by that UIColor, but ARC will deallocate the UIColor before you have a chance to use the CGColor.
The clearest solution is to have a local variable pointing to your UIColor with the objc_precise_lifetime attribute.
You can read more about this exact cas...
git diff two files on same branch, same commit
... but the fact that he mentions BeyondCompare implies that he's not specifically looking for a git diff but simply an easy to read diff. Also the fact he accepted my answer as what he was looking for also indicates that it does in fact answer it.
– JaredMcAteer
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MySQL Cannot Add Foreign Key Constraint
...storyID is an INT, Patient.MedicalHistory also needs to be an INT, not a SMALLINT.
Also, you should run the query set foreign_key_checks=0 before running the DDL so you can create the tables in an arbitrary order rather than needing to create all parent tables before the relevant child tables.
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