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Mathematical functions in Swift
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UIKit, Cocoa, Foundation, all valid choices.
– erdekhayser
Nov 27 '14 at 20:26
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How does type Dynamic work and how to use it?
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Scalas type Dynamic allows you to call methods on objects that don't exist or in other words it is a replica of "method missing" in dynamic languages.
It is correct, scala.Dynamic doesn't have any members, it is just a marker interface - the co...
How to delete a file via PHP?
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Check your permissions first of all on the file, to make sure you can a) see it from your script, and b) are able to delete it.
You can also use a path calculated from the directory you're currently running the script in, eg:
unlink(dirname(__FILE__) . "/...
How to get the error message from the error code returned by GetLastError()?
After a Windows API call, how can I get the last error message in a textual form?
11 Answers
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Is there a way to crack the password on an Excel VBA Project?
...y best to explain how it works - please excuse my English.
The VBE will call a system function to create the password dialog box.
If user enters the right password and click OK, this function returns 1. If user enters the wrong password or click Cancel, this function returns 0.
After the dialog bo...
Undefined symbols for architecture i386: _OBJC_CLASS_$_SKPSMTPMessage", referenced from: error
...r the "Compile Sources" step of the "Build Phases" tab of your target. Normally Xcode does this for you, but sometimes it loses the plot and you need to add the .m file manually.
To do this:
TargetSettings -> Build Phases -> Compile Sources -> add your .m class ->Build and Run
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When to use enumerateObjectsUsingBlock vs. for
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Ultimately, use whichever pattern you want to use and comes more naturally in the context.
While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting:
enumerateObjectsUsingBlock: will be as fas...
How to remove non-alphanumeric characters?
I need to remove all characters from a string which aren't in a-z A-Z 0-9 set or are not spaces.
9 Answers
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add column to mysql table if it does not exist
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OK this is really crude but someone's got to say it. if you are simply running a SQL script from the command line, you can give mysql the --force switch, which means keep going even if there's an error. then, just go for it. you just want...
Comma in C/C++ macro
...his is also a problem for square brackets and braces, even though those usually occur as balanced pairs.) You can enclose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remains parenthesized inside the macro expansion, which pr...