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How to Apply Gradient to background view of iOS Swift App
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I'm getting this error fatal error: array element cannot be bridged to Objective-C, when assigning to .colors property. What may be wrong with this?
– Tricertops
Jul 20 '14 at 19:10
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How to decide font color in white or black depending on background color?
...ove.
The formula given for contrast in the W3C Recommendations is (L1 + 0.05) / (L2 + 0.05), where L1 is the luminance of the lightest color and L2 is the luminance of the darkest on a scale of 0.0-1.0. The luminance of black is 0.0 and white is 1.0, so substituting those values lets you determine ...
Regex to match only letters
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with python 3 this yields an error bad escape \p at position 0
– matanster
Apr 19 '19 at 16:23
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How do I get the number of elements in a list?
...objects with a "size" in Python, in particular, have an attribute called ob_size, where the number of elements in the object is cached. So checking the number of objects in a list is very fast.
But if you're checking if list size is zero or not, don't use len - instead, put the list in a boolean co...
Passing arguments to C# generic new() of templated type
...ll, and somebody might try to "clean up" and delete it (to cause a runtime error at some random time in the future). You may want to consider adding a dummy function where you use this constructor just so you get a compile error if you try to delete it.
– jrh
O...
How to iterate through two lists in parallel?
...e?
– Charlie Parker
Mar 6 '18 at 18:05
2
@CharlieParker: Yes you can, but then you would use for ...
Check variable equality against a list of values
...s. For special characters is becomes ugly due to escaping and is also more error-prone due to that.
/foo|bar|something/.test(str);
To be more precise, this will check the exact string, but then again is more complicated for a simple equality test:
/^(foo|bar|something)$/.test(str);
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Better way to get type of a Javascript variable?
...[object Array]' : 'array',
'[object Date]' : 'date',
'[object Error]' : 'error'
},
TOSTRING = Object.prototype.toString;
function type(o) {
return TYPES[typeof o] || TYPES[TOSTRING.call(o)] || (o ? 'object' : 'null');
};
This captures many of the primitives provided by javascri...
How to write log to file
....O_RDWR | os.O_CREATE | os.O_APPEND, 0666)
if err != nil {
log.Fatalf("error opening file: %v", err)
}
defer f.Close()
log.SetOutput(f)
log.Println("This is a test log entry")
Based on the Go docs, os.Open() can't work for log.SetOutput, because it opens the file "for reading:"
func Open
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What is a typedef enum in Objective-C?
...mple:
enum tagname x; // declare x of type 'enum tagname'
tagname x; // ERROR in C/Objective-C, OK in C++
In order to avoid having to use the enum keyword everywhere, a typedef can be created:
enum tagname { ... };
typedef enum tagname tagname; // declare 'tagname' as a typedef for 'enum tagn...