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How do I remove a property from a JavaScript object?
...t object, then that object will, of course, not be garbage collected until all references to it have disappeared.
delete will only work on properties whose descriptor marks them as configurable.
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Are there any reasons to use private properties in C#?
...et
{
if (_password == null)
{
_password = CallExpensiveOperation();
}
return _password;
}
}
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Execute a terminal command from a Cocoa app
...;
NSFileHandle *file = pipe.fileHandleForReading;
NSTask *task = [[NSTask alloc] init];
task.launchPath = @"/usr/bin/grep";
task.arguments = @[@"foo", @"bar.txt"];
task.standardOutput = pipe;
[task launch];
NSData *data = [file readDataToEndOfFile];
[file closeFile];
NSString *grepOutput = [[NSS...
ActiveRecord: size vs count
...l valid.
You'll adapt the function you use depending on your needs.
Basically:
if you already load all entries, say User.all, then you should use length to avoid another db query
if you haven't anything loaded, use count to make a count query on your db
if you don't want to bother with these con...
Naming cookies - best practices [closed]
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@Emanuil: To distinguish it from all the other cookies generated by other apps on the same domain.
– Ignacio Vazquez-Abrams
Sep 19 '12 at 20:50
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Getting the first character of a string with $str[0]
...am just not sure whether this is 'good practice', as that notation is generally used with arrays. This feature doesn't seem to be very well documented so I'm turning to you guys to tell me if it's all right – in all respects – to use this notation?
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Add alternating row color to SQL Server Reporting services report
...t when the basic solution does not suffice, it's a nice alternative.
Basically, you add code to the Report as follows...
Private bOddRow As Boolean
'*************************************************************************
' -- Display green-bar type color banding in detail rows
' -- Call from Bac...
In Python, how can you load YAML mappings as OrderedDicts?
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Update: In python 3.6+ you probably don't need OrderedDict at all due to the new dict implementation that has been in use in pypy for some time (although considered CPython implementation detail for now).
Update: In python 3.7+, the insertion-order preservation nature of dict objects h...
What's the difference between TRUNCATE and DELETE in SQL
...nces highlighted below.
General Overview
If you want to quickly delete all of the rows from a table, and you're really sure that you want to do it, and you do not have foreign keys against the tables, then a TRUNCATE is probably going to be faster than a DELETE.
Various system-specific issues h...
how to ignore namespaces with XPath
...re sometimes client-generated i.e. unknown to me. Then i am left with basically three choices :
5 Answers
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