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How to split a string literal across multiple lines in C / Objective-C?
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There are two ways to split strings over multiple lines:
Using \
All lines in C can be split into multiple lines using \.
Plain C:
char *my_string = "Line 1 \
Line 2";
Objective-C:
NSString *my_string = @"Line1 \
Line2";
Better approach
Th...
JavaScript Regular Expression Email Validation [duplicate]
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If you define your regular expression as a string then all backslashes need to be escaped, so instead of '\w' you should have '\\w'.
Alternatively, define it as a regular expression:
var pattern = /^\w+@[a-zA-Z_]+?\.[a-zA-Z]{2,3}$/;
BTW, please don't validate email address...
select * vs select column
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It always pulls a tuple (except in cases where the table has been vertically segmented - broken up into columns pieces), so, to answer the question you asked, it doesn't matter from a performance perspective. However, for many other reasons, (below) you should always select specifically those co...
Can you find all classes in a package using reflection?
Is it possible to find all classes or interfaces in a given package? (Quickly looking at e.g. Package , it would seem like no.)
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Deleting a resource using http DELETE
...DELETE as an idempotent
operation requires the server to keep
track of all deleted resources.
Otherwise, it can return a 404 (Not
Found).
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how to use javascript Object.defineProperty
...rs = new Product("Sneakers",20);
sneakers.discount = 50; // 50, setter is called
sneakers.discount+= 20; // 70, setter is called
sneakers.discount+= 20; // 80, not 90!
alert(sneakers.discount); // getter is called
Note the last but one line: the responsibility for correct discount value was moved ...
Calculating frames per second in a game
... mean the value of time that you calculated for the last frame. This way, all previous frames will be included, with the most recent frames weighted the most heavily.
– j_random_hacker
May 23 '13 at 20:37
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performSelector may cause a leak because its selector is unknown
...for the C function pointer for the method corresponding to the controller. All NSObjects respond to methodForSelector:, but you can also use class_getMethodImplementation in the Objective-C runtime (useful if you only have a protocol reference, like id<SomeProto>). These function pointers are ...
What do (lambda) function closures capture?
...the name and scope of the variable, not the object it's pointing to. Since all the functions in your example are created in the same scope and use the same variable name, they always refer to the same variable.
EDIT: Regarding your other question of how to overcome this, there are two ways that com...
Printf width specifier to maintain precision of floating-point value
...ier which can be applied to a floating point specifier that would automatically format the output to the necessary number of significant digits such that when scanning the string back in, the original floating point value is acquired?
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