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How can I determine if a variable is 'undefined' or 'null'?
...enceError and break execution if variable is not defined or referred to at all in the code, using typeof is safer.
– Mani Gandham
Jun 15 '14 at 9:49
59
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Test whether string is a valid integer
...
Additionally, based on character collation (see this related question/answer) something like d[g-i]{2} could end up not only matching dig but also dish in the collation suggested by that answer (where the sh digraph is considered a s...
Django: Set foreign key using integer?
...
Yep:
employee = Employee(first_name="Name", last_name="Name")
employee.type_id = 4
employee.save()
ForeignKey fields store their value in an attribute with _id at the end, which you can access directly to avoid visiting the database.
The _id version of...
How to give ASP.NET access to a private key in a certificate in the certificate store?
...Local Computer" account. Best to use Certificates MMC. Make sure to check "Allow private key to be exported"
Based upon which, IIS 7.5 Application Pool's identity use one of the following.
IIS 7.5 Website is running under ApplicationPoolIdentity. Open MMC => Add Certificates (Local computer) sn...
MVC Razor dynamic model, 'object' does not contain definition for 'PropertyName'
...:
According to David Ebbo, you can't pass an anonymous type into a dynamically-typed view because the anonymous types are compiled as internal. Since the CSHTML view is compiled into a separate assembly, it can't access the anonymous type's properties.
EDIT #2:
David Ebbo has edited his post with...
How to check if hex color is “too black”?
...
You have to extract the three RGB components individually, and then use a standard formula to convert the resulting RGB values into their perceived brightness.
Assuming a six character colour:
var c = c.substring(1); // strip #
var rgb = parseInt(c, 16); // convert rrg...
Changing Vim indentation behavior by file type
...h a width of 2 characters for indenting (the noexpandtab option is set globally elsewhere in my configuration).
This is described here: http://vimdoc.sourceforge.net/htmldoc/usr_05.html#05.4, scroll down to the section on filetype plugins.
...
Obtain Bundle Identifier programmatically
...n approach to get the value. ARC example is following:
NSString *value = (__bridge_transfer NSString *)CFDictionaryGetValue(CFBundleGetInfoDictionary(CFBundleGetMainBundle()),
(const void *)(@"CFBundleIdentifier"));
...
Can anyone explain CreatedAtRoute() to me?
...ss CompanyController : Controller
{
private ICompanyRepository _companyRepository;
public CompanyController(ICompanyRepository companyRepository)
{
_companyRepository = companyRepository;
}
[HttpGet("{id}", Name="GetCompany")]
public ...
How to randomize (or permute) a dataframe rowwise and columnwise?
...] 1 0 0 1 0
[4,] 0 0 1 0 1
To explain the call:
out <- permatswap(mat, times = 99, burnin = 20000, thin = 500, mtype = "prab")
times is the number of randomised matrices you want, here 99
burnin is the number of swaps made before we start taking random samples....