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Does anyone know what the new Exit icon is used for when editing storyboards using Xcode 4.5?
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220
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Why is a div with “display: table-cell;” not affected by margin?
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21
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Why does ~True result in -2?
...True) is 1.
1 is:
00000001
and ~1 is:
11111110
Which is -2 in Two's complement1
1 Flip all the bits, add 1 to the resulting number and interpret the result as a binary representation of the magnitude and add a negative sign (since the number begins with 1):
11111110 → 00000001 → 0000001...
How can I combine hashes in Perl?
What is the best way to combine both hashes into %hash1? I always know that %hash2 and %hash1 always have unique keys. I would also prefer a single line of code if possible.
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Android onCreate or onStartCommand for starting service
...d, but in my last project this does not work. I tried implementing onStartCommand , and this seems to work.
2 Answers
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Bash, no-arguments warning, and case decisions
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You mean the errors coming out of a particular program you're calling? You can put > /dev/null and/or 2> /dev/null after that to send its standard output and/or standard error streams into oblivion.
– Thomas
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How to move columns in a MySQL table?
...loyees MODIFY COLUMN empName VARCHAR(50) AFTER department;
EDIT
Per the comments, you can also do this:
ALTER TABLE Employees CHANGE COLUMN empName empName VARCHAR(50) AFTER department;
Note that the repetition of empName is deliberate. You have to tell MySQL that you want to keep the same col...
How to convert hashmap to JSON object in Java
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This only works for a String,String map and not a complex String,Object.
– slott
Nov 28 '13 at 13:34
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GitHub “fatal: remote origin already exists”
...d just update the existing remote:
$ git remote set-url origin git@github.com:ppreyer/first_app.git
Long version:
As the error message indicates, there is already a remote configured with the same name. So you can either add the new remote with a different name or update the existing one if you ...
How do I check the difference, in seconds, between two dates?
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if you want to compute differences between two known dates, use total_seconds like this:
import datetime as dt
a = dt.datetime(2013,12,30,23,59,59)
b = dt.datetime(2013,12,31,23,59,59)
(b-a).total_seconds()
86400.0
#note that seconds ...