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How to check if a file exists in the Documents directory in Swift?
...ite")
Now check if the file exists with checkResourceIsReachableAndReturnError of NSURL.
let fileExists = databaseURL.checkResourceIsReachableAndReturnError(nil)
If you need the error pass the NSError pointer to the parameter.
var error : NSError?
let fileExists = databaseURL.checkResourceIsR...
Downcasting in Java
Upcasting is allowed in Java, however downcasting gives a compile error.
11 Answers
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Checking if jquery is loaded using Javascript
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This will still throw an error as is when jQuery is undefined. You need check for window.jQuery.
– gilly3
Sep 8 '11 at 0:23
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When to use RDLC over RDL reports?
...things to think about both things:
I. RDL reports are HOSTED reports generally. This means you need to implement SSRS Server. They are a built in extension of Visual Studio from SQL Server for the reporting language. When you install SSRS you should have an add on called 'Business Intelligence D...
Using getopts to process long and short command line options
...comes with caveats:
getopts can't enforce the opt spec. It can't return errors if the user supplies an invalid option. You have to do your own error-checking as you parse OPTARG.
OPTARG is used for the long option name, which complicates usage when your long option itself has an argument. You end...
Why does the PHP json_encode function convert UTF-8 strings to hexadecimal entities?
...e in earlier versions. When using it in earlier versions you will get this error: "Warning: json_encode() expects parameter 2 to be long, string given in ...". See CertaiN's answer below for 5.3 solution.
– Octavian Naicu
Oct 1 '14 at 10:03
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Git command to show which specific files are ignored by .gitignore
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What version of git are you using? Mine (1.7.0.4) says error: unknown option 'ignored'. Even adding -s as suggested in linked post didn't work.
– Alexander Bird
Oct 25 '12 at 21:49
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PowerShell says “execution of scripts is disabled on this system.”
... file that calls a PowerShell script from cmd.exe , but I am getting this error:
32 Answers
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How can I default a parameter to Guid.Empty in C#?
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Explanation
Why didn't Guid.Empty work?
The reason you are getting the error is because Empty is defined as:
public static readonly Guid Empty;
So, it is a variable, not a constant (defined as static readonly not as const). Compiler can only have compiler-known values as method parameters def...
Why does auto a=1; compile in C?
...CC and Clang both warn about it in C99 mode, but they don't consider it an error except with -Werror.
– Fred Foo
May 1 '14 at 12:12
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