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ARC and bridged cast
With ARC, I can no longer cast CGColorRef to id . I learned that I need to do a bridged cast. According clang docs :
3 ...
Java generics T vs Object
...ct
Foo newFoo = (Foo) my.doSomething(foo);
Two advantages:
no need of casting (the compiler hides this from you)
compile time safety that works. If the Object version is used, you won't be sure that the method always returns Foo. If it returns Bar, you'll have a ClassCastException, at runtime.
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Can an enum class be converted to the underlying type?
...you can use std::underlying_type to know the underlying type, and then use cast:
#include <type_traits> //for std::underlying_type
typedef std::underlying_type<my_fields>::type utype;
utype a = static_cast<utype>(my_fields::field);
With this, you don't have to assume the under...
What datatype to use when storing latitude and longitude data in SQL databases? [duplicate]
...o do a lot of calculations, and can show that rounding errors matter, then cast to 64-bit float first.
– nilskp
Jul 2 '13 at 15:09
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Test if string is a number in Ruby on Rails
...ds on the ratio of false cases expected.
If they are relatively uncommon casting is definitely fastest.
If false cases are common and you are just checking for ints, comparison vs a transformed state is a good option.
If false cases are common and you are checking floats, regexp is probably the wa...
Change type of varchar field to integer: “cannot be cast automatically to type integer”
...rying ". I'm trying to change it to " Integer " but it gives an error that casting is not possible.
8 Answers
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How to round an average to 2 decimal places in PostgreSQL?
... | numeric, integer | normal
(4 rows)
regress=> SELECT round( CAST(float8 '3.1415927' as numeric), 2);
round
-------
3.14
(1 row)
(In the above, note that float8 is just a shorthand alias for double precision. You can see that PostgreSQL is expanding it in the output).
You must c...
is it possible to select EXISTS directly as a bit?
...und.
If you must return a conditional bit 0/1 another way is to:
SELECT CAST(
CASE WHEN EXISTS(SELECT * FROM theTable where theColumn like 'theValue%') THEN 1
ELSE 0
END
AS BIT)
Or without the cast:
SELECT
CASE
WHEN EXISTS( SELECT 1 FROM theTable WHERE theColumn LIKE 'the...
Concept of void pointer in C programming
Is it possible to dereference a void pointer without type-casting in the C programming language?
15 Answers
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Is it possible to cast a Stream in Java 8?
Is it possible to cast a stream in Java 8? Say I have a list of objects, I can do something like this to filter out all the additional objects:
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