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Undefined symbols for architecture i386: _OBJC_CLASS_$_SKPSMTPMessage", referenced from: error
... target. Normally Xcode does this for you, but sometimes it loses the plot and you need to add the .m file manually.
To do this:
TargetSettings -> Build Phases -> Compile Sources -> add your .m class ->Build and Run
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EF Code First “Invalid column name 'Discriminator'” but no inheritance
...he CREATE TABLE statement). It has a primary key, a couple of foreign keys and nothing special about it. I have many tables in my database similar to that one, but for some reason, this table ended up with a "Discriminator" column on the EF Proxy Class.
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Why covariance and contravariance do not support value type
...or not.
You might want to read Eric Lippert's blog post on representation and identity for more on this topic in general.
EDIT: Having reread Eric's blog post myself, it's at least as much about identity as representation, although the two are linked. In particular:
This is why covariant and ...
parseInt(null, 24) === 23… wait, what?
Alright, so I was messing around with parseInt to see how it handles values not yet initialized and I stumbled upon this gem. The below happens for any radix 24 or above.
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C# switch statement limitations - why?
...t the same
thing as a big if-else statement.
Each case must be unique and evaluated
statically. The switch statement does
a constant time branch regardless of
how many cases you have. The if-else
statement evaluates each condition
until it finds one that is true.
In fact, the C#...
How to check BLAS/LAPACK linkage in NumPy and SciPy?
I am builing my numpy/scipy environment based on blas and lapack more or less based on this walk through.
5 Answers
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FileSystemWatcher Changed event is raised twice
I have an application where I am looking for a text file and if there are any changes made to the file I am using the OnChanged eventhandler to handle the event. I am using the NotifyFilters.LastWriteTime but still the event is getting fired twice. Here is the code.
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What is the difference between . (dot) and $ (dollar sign)?
What is the difference between the dot (.) and the dollar sign ($) ?
13 Answers
13
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How can I perform a culture-sensitive “starts-with” operation from the middle of a string?
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I'll consider the problem of many<->one/many casemappings first and separately from handling different Normalization forms.
For example:
x heiße y
^--- cursor
Matches heisse but then moves cursor 1 too much. And:
x heisse y
^--- cursor
Matches heiße but then moves cursor 1 to...
How to avoid having class data shared among instances?
...ring the variables inside the class declaration makes them "class" members and not instance members. Declaring them inside the __init__ method makes sure that a new instance of the members is created alongside every new instance of the object, which is the behavior you're looking for.
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