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Using unset vs. setting a variable to empty
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var= is not "not set". It's just an unquoted empty string. In addition to set -u, bash's various forms of parameter expansion can also distinguish between unset and null values: ${foo:bar} expands to "bar" when foo is unset, but "" when foo is null, while ${foo:-bar} expands ...
How to get the month name in C#?
...nsole.Read();
}
}
static class DateTimeExtensions
{
public static string ToMonthName(this DateTime dateTime)
{
return CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(dateTime.Month);
}
public static string ToShortMonthName(this DateTime dateTime)
{
re...
JavaScript isset() equivalent
...= { foo: 'bar'};
obj.hasOwnProperty('foo'); // true
obj.hasOwnProperty('toString'); // false
'toString' in obj; // true
As you can see, hasOwnProperty returns false and the in operator returns true when checking the toString method, this method is defined up in the prototype chain, because obj in...
PostgreSQL query to return results as a comma separated list
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SELECT string_agg(id::text, ',') FROM table
Requires PostgreSQL 9.0 but that's not a problem.
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How do I render a partial of a different format in Rails?
...de of this approach is that localizations will look for foo.baz.html.[your_string] instead of foo.baz.[your_string]. zgchurc's answer is a better solution.
– mbillard
Jul 23 '12 at 13:44
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Where are the PostgreSQL logs on macOS?
...>
<dict>
[...]
<key>StandardErrorPath</key>
<string>/usr/local/var/postgres/server.log</string>
</dict>
</plist>
So in this case, /usr/local/var/postgres/server.log.
share...
Does functional programming replace GoF design patterns?
...ome pretty funny attempts at F#, where literally every function was just a string of 'let' statements, basically as if you'd taken a C program, and replaced all semicolons with 'let'. :))
But another possibility might be that you just haven't realized that you're solving problems trivially which wo...
Is < faster than
... will not be faster on most architectures. You didn't specify, but on x86, all of the integral comparisons will be typically implemented in two machine instructions:
A test or cmp instruction, which sets EFLAGS
And a Jcc (jump) instruction, depending on the comparison type (and code layout):
jne ...
How to convert an NSTimeInterval (seconds) into minutes
...to convert a given NSTimeInterval from its value in seconds to a localized string to show the user. For example:
Objective-C
NSTimeInterval interval = 326.4;
NSDateComponentsFormatter *componentFormatter = [[NSDateComponentsFormatter alloc] init];
componentFormatter.unitsStyle = NSDateComponents...
SQLite - replace part of a string
Is it possible using SQL in an SQLite table to replace part of a string?
3 Answers
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