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What is the best way to test for an empty string in Go?
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10 Answers
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SQL how to increase or decrease one for a int column in one command
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answered Jun 10 '09 at 2:01
gahooagahooa
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An error occurred while installing pg (0.17.1), and Bundler cannot continue
I just installed Rails 4.0.2 and when creating a new app, in the bundle stage I get:
16 Answers
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Test whether string is a valid integer
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[[ $var =~ ^-?[0-9]+$ ]]
The ^ indicates the beginning of the input pattern
The - is a literal "-"
The ? means "0 or 1 of the preceding (-)"
The + means "1 or more of the preceding ([0-9])"
The $ indicates the end of the input pattern
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PHP regular expressions: No ending delimiter '^' found in
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PHP regex strings need delimiters. Try:
$numpattern="/^([0-9]+)$/";
Also, note that you have a lower case o, not a zero. In addition, if you're just validating, you don't need the capturing group, and can simplify the regex to /^\d+$/.
Example: http://ideone.com/Ec3zh
See also:...
How to count items in a Go map?
...ed from the now-retired SO documentation:
m := map[string]int{}
len(m) // 0
m["foo"] = 1
len(m) // 1
If a variable points to a nil map, then len returns 0.
var m map[string]int
len(m) // 0
Excerpted from Maps - Counting map elements. The original author was Simone Carletti. Attribution det...
Determine installed PowerShell version
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+50
Use $PSVersionTable.PSVersion to determine the engine version. If the variable does not exist, it is safe to assume the engine is vers...
This project references NuGet package(s) that are missing on this computer
...hem. For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
</PropertyGroup>
<Error Condition="!Exists('$(SolutionDir)\.nuget\NuGet.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(SolutionDir)\.nuget\NuGet.targe...
How do I apply a perspective transform to a UIView?
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330
As Ben said, you'll need to work with the UIView's layer, using a CATransform3D to perform the l...
Extracting Nupkg files using command line
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106
You can also use the NuGet command line, by specifying a local host as part of an install. For ...