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Why does !{}[true] evaluate to true in JavaScript?
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I believe that's because plain {}[true] is parsed as an empty statement block (not an object literal) followed by an array containing true, which is true.
On the other hand, applying the ! operator makes the parser interpret {} as an object literal, so...
Safely remove migration In Laravel
In Laravel, there appears to be a command for creating a migration, but not removing.
9 Answers
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Configure Microsoft.AspNet.Identity to allow email address as username
I'm in the process of creating a new application and started out using EF6-rc1, Microsoft.AspNet.Identity.Core 1.0.0-rc1, Microsoft.AspNet.Identity.EntityFramework 1.0.0-rc1, Microsoft.AspNet.Identity.Owin 1.0.0-rc1, etc and with the RTM releases yesterday, I updated them via NuGet this evening to R...
jQuery 'input' event
I've never heard of an event in jQuery called input till I saw this jsfiddle .
8 Answers
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“Parser Error Message: Could not load type” in Global.asax
I'm working on an MVC3 project and receive the following error:
35 Answers
35
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“ValueError: zero length field name in format” error in Python 3.0,3.1,3.2
I'm trying learn Python (3 to be more specific) and I'm getting this error:
3 Answers
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Get model's fields in Django
Given a Django model, I'm trying to list all of its fields. I've seen some examples of doing this using the _meta model attribute, but doesn't the underscore in front of meta indicate that the _meta attribute is a private attribute and shouldn't be accessed directly? ... Because, for example, the ...
Is there a function to make a copy of a PHP array to another?
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In PHP arrays are assigned by copy, while objects are assigned by reference. This means that:
$a = array();
$b = $a;
$b['foo'] = 42;
var_dump($a);
Will yield:
array(0) {
}
Whereas:
$a = new StdClass();
$b = $a;
$b->...
ALTER TABLE without locking the table?
When doing an ALTER TABLE statement in MySQL, the whole table is read-locked (allowing concurrent reads, but prohibiting concurrent writes) for the duration of the statement. If it's a big table, INSERT or UPDATE statements could be blocked for a looooong time. Is there a way to do a "hot alter", li...
How should I escape commas and speech marks in CSV files so they work in Excel?
I'm generating a CSV file (delimited by commas rather than tabs). My users will most likely open the CSV file in Excel by double clicking it. My data may contain commas and speech marks, so I'm escaping those as follows.
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