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Django - Circular model import issue
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Remove the import of Theme and use the model name as a string instead.
theme = models.ForeignKey('themes.Theme')
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How do I get the name of a Ruby class?
... For the newcomers out there, you can also obtain the class name as a string by using the class like this: User.name. User.to_s also seems to work.
– Dan Polites
Nov 20 '12 at 20:17
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How to JSON serialize sets?
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JSON notation has only a handful of native datatypes (objects, arrays, strings, numbers, booleans, and null), so anything serialized in JSON needs to be expressed as one of these types.
As shown in the json module docs, this conversion can be done automatically by a JSONEncoder and JSONDecoder,...
in entity framework code first, how to use KeyAttribute on multiple columns
...t MySecondKeyProperty { get; set; }
[Key, Column(Order=2)]
public string MyThirdKeyProperty { get; set; }
// other properties
}
If you are using the Find method of a DbSet you must take this order for the key parameters into account.
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Hibernate: hbm2ddl.auto=update in production?
...erstand when datatypes for columns have changed. Examples (using MySQL):
String with @Column(length=50) ==> varchar(50)
changed to
String with @Column(length=100) ==> still varchar(50), not changed to varchar(100)
@Temporal(TemporalType.TIMESTAMP,TIME,DATE) will not update the DB columns i...
Which regular expression operator means 'Don't' match this character?
...mer: don't match a, b, c or 0: [^a-c0]
The latter: match any three-letter string except foo and bar:
(?!foo|bar).{3}
or
.{3}(?<!foo|bar)
Also, a correction for you: *, ? and + do not actually match anything. They are repetition operators, and always follow a matching operator. Thus, a+ means...
What is a correct mime type for docx, pptx etc?
...MimeMapping(yourFileName) to get MIME types - much better than hard-coding strings
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How can I change the color of AlertDialog title and the color of the line under it
...erent color for the title or divider, you use the following code:
private String HALLOWEEN_ORANGE = "#FF7F27";
QustomDialogBuilder qustomDialogBuilder = new QustomDialogBuilder(v.getContext()).
setTitle("Set IP Address").
setTitleColor(HALLOWEEN_ORANGE).
setDividerColor(HALLOWEEN_ORANG...
What does %~dp0 mean, and how does it work?
... search, then this modifier expands to the
empty string
The modifiers can be combined to get
compound results:
%~dpI - expands %I to a drive letter and path only
%~nxI - expands %I to a file name and extension only
%~fsI - expands %I to a full pat...
Double not (!!) operator in PHP
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This means that for any true value (numbers other than zero, non-empty strings and arrays, etc.) you will get the boolean value TRUE, and for any false value (0, 0.0, NULL, empty strings or empty arrays) you will get the boolean value FALSE.
It is functionally equivalent to a cast to boolean:
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