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How to get the first element of the List or Set? [duplicate]
I'd like to know if I can get the first element of a list or set. Which method to use?
9 Answers
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What is the difference between the | and || or operators?
I have always used || (two pipes) in OR expressions, both in C# and PHP. Occasionally I see a single pipe used: | . What is the difference between those two usages? Are there any caveats when using one over the other or are they interchangeable?
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Evaluate empty or null JSTL c tags
How can I validate if a String is null or empty using the c tags of JSTL ?
8 Answers
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IF… OR IF… in a windows batch file
Is there a way to write an IF OR IF conditional statement in a windows batch-file?
14 Answers
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Is there an easy way to check the .NET Framework version?
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Something like this should do it. Just grab the value from the registry
For .NET 1-4:
Framework is the highest installed version, SP is the service pack for that version.
RegistryKey installed_versions = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP");
string[] ve...
When can I use a forward declaration?
I am looking for the definition of when I am allowed to do forward declaration of a class in another class's header file:
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Does Python support short-circuiting?
Does Python support short-circuiting in boolean expressions?
3 Answers
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commandButton/commandLink/ajax action/listener method not invoked or input value not set/updated
Sometimes, when using <h:commandLink> , <h:commandButton> or <f:ajax> , the action , actionListener or listener method associated with the tag are simply not being invoked. Or, the bean properties are not updated with submitted UIInput values.
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How can I check if a string is null or empty in PowerShell?
Is there a built-in IsNullOrEmpty -like function in order to check if a string is null or empty, in PowerShell?
11 Answers...
Programmatically Lighten or Darken a hex color (or rgb, and blend colors)
Here is a function I was working on to programmatically lighten or darken a hex color by a specific amount. Just pass in a string like "3F6D2A" for the color ( col ) and a base10 integer ( amt ) for the amount to lighten or darken. To darken, pass in a negative number (i.e. -20 ).
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