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Should I use #define, enum or const?
...Assuming you have ruled out bitset, I vote for the enum.
I don't buy that casting the enums is a serious disadvantage - OK so it's a bit noisy, and assigning an out-of-range value to an enum is undefined behaviour so it's theoretically possible to shoot yourself in the foot on some unusual C++ impl...
Java array reflection: isArray vs. instanceof
...er an object is an array.
Generally, you test an object's type before downcasting to a particular type which is known at compile time. For example, perhaps you wrote some code that can work with a Integer[] or an int[]. You'd want to guard your casts with instanceof:
if (obj instanceof Integer[]) ...
How to export all data from table to an insertable sql format?
...nvarchar (max) = ''
DECLARE @Columns nvarchar(max)
DECLARE @ColumnsCast nvarchar(max)
-- cleanUp/prepraring data
SET @SchemaName = REPLACE(REPLACE(@SchemaName,'[',''),']','')
SET @TableName = REPLACE(REPLACE(@TableName,'[',''),']','')
SET @AsFileNAme = NULLIF(@AsFileNAme,'')...
Detect if value is number in MySQL
...('12.e-5'),('3.5e+6'),('a'),('e6'),('+e0');
select
col1,
col1 + 0 as casted,
col1 REGEXP '^[+-]?[0-9]*([0-9]\\.|[0-9]|\\.[0-9])[0-9]*(e[+-]?[0-9]+)?$' as isNumeric
from myTable;
Result:
col1 | casted | isNumeric
-------|---------|----------
00.00 | 0 | 1
+1 | 1...
php is null or empty?
... @Robert: A string not starting with digits is converted to 0 when cast to a string: codepad.org/qi40SG3E. So (int)"php" == 0.
– Felix Kling
Nov 27 '13 at 21:58
...
What is the best way to prevent session hijacking?
... when a user visits one of your "sensitive" areas, redirect them to HTTPS, and check for the presence of that secure cookie. A real user will have it, a session hijacker will not.
EDIT: This answer was originally written in 2008. It's 2016 now, and there's no reason not to have SSL across your enti...
How can mixed data types (int, float, char, etc) be stored in an array?
... x = r;
x.val = 25.0;
}
integer g = { INT, 100 };
record rg = g;
Up-casting and down-casting.
Edit: One gotcha to be aware of is if you're constructing one of these with C99 designated initializers. All member initializers should be through the same union member.
record problem = { .tag ...
What is the strict aliasing rule?
... struct onto such a buffer, or a buffer onto such a struct through pointer casting you can easily violate strict aliasing rules.
So in this kind of setup, if I want to send a message to something I'd have to have two incompatible pointers pointing to the same chunk of memory. I might then naively co...
Getting a better understanding of callback functions in JavaScript
...
Why do you cast callback to string and then check its type? Will this enhance performance? This is like checking the type, checking if the converted boolean returns true and then checking its type again and testing it against the string...
Get an object's class name at runtime
...
@Subash a terser way to avoid casting to any is console.log(instance.constructor['name']);
– Nick Strupat
Sep 2 '16 at 7:47
1
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