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Unable to generate an explicit migration in entity framework
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It tells you that there is some unprocessed migration in your application and it requires running Update-Database before you can add another migration.
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When can I use a forward declaration?
...ssuming the following forward declaration.
class X;
Here's what you can and cannot do.
What you can do with an incomplete type:
Declare a member to be a pointer or a reference to the incomplete type:
class Foo {
X *p;
X &r;
};
Declare functions or methods which accept/return inco...
Formatting Phone Numbers in PHP
I am working on an SMS app and need to be able to convert the sender's phone number from +11234567890 to 123-456-7890 so it can be compared to records in a MySQL database .
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Is it Linq or Lambda?
...ice by allowing you to express your wishes in the manner that you prefer.
And this is a lambda:
x => x.Value == 1
When you choose to use method syntax, LINQ is almost always seen around lambda expressions. But LINQ and lambdas are two totally different things, both of which can be used by the...
Is JavaScript an untyped language?
... talked about in one of the above answers - the runtime doesn't tag values and just treats each value as bits. JavaScript does tag values and has different behaviour based on those tags. So JavaScript obviously doesn't fit this category.
The other definition is from Programming Language Theory (the ...
What is the difference between ~> and >= when specifying rubygem in Gemfile?
...constraint. RubyGems will increment the last digit in the version provided and use that until it reaches a maximum version. So ~>0.8.5 is semantically equivalent to:
gem "cucumber", ">=0.8.5", "<0.9.0"
The easy way to think about it is that you're okay with the last digit incrementing to ...
HTTP 1.0 vs 1.1
...ould somebody give me a brief overview of the differences between HTTP 1.0 and HTTP 1.1? I've spent some time with both of the RFCs, but haven't been able to pull out a lot of difference between them. Wikipedia says this:
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Fastest way to determine if record exists
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@Declan_K: seems like my magic sphere failed in this case and a column entitled as id isn't PK. So +1 to your advice.
– zerkms
Aug 7 '13 at 22:00
4
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Make xargs execute the command once for each line of input
How can I make xargs execute the command exactly once for each line of input given?
It's default behavior is to chunk the lines and execute the command once, passing multiple lines to each instance.
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lock(new object()) — Cargo cult or some crazy “language special case”?
I'm reviewing some code written by a consultant, and while dozens of red flags have already popped up, I can't wrap my head around the following snippet:
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