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Why don't structs support inheritance?
... The sensible solution to that problem would be to disallow the cast form Base[] to Detived[]. Just like casting from short[] to int[] is forbidden, although casting from short to int is possible.
– Niki
Aug 3 '09 at 16:34
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$_POST vs. $_SERVER['REQUEST_METHOD'] == 'POST'
...ts regardless if the request was sent with POST headers. An empty array is cast to false in a boolean check.
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How to get the caller's method name in the called method?
...ccessing.
import inspect
from types import FrameType
from typing import cast
def caller_name() -> str:
"""Return the calling function's name."""
# Ref: https://stackoverflow.com/a/57712700/
return cast(FrameType, cast(FrameType, inspect.currentframe()).f_back).f_code.co_name
if...
What are POD types in C++?
...en pointers to vtables, offsets that get applied to the address when it is cast to other types (at least if the target's POD too), constructors, or destructors. Roughly speaking, a type is a POD when the only things in it are built-in types and combinations of them. The result is something that "act...
How do you list the primary key of a SQL Server table?
...rimary Key and Foreign Keys ) and at the end of query put table name
/* CAST IS DONE , SO THAT OUTPUT INTEXT FILE REMAINS WITH SCREEN LIMIT*/
WITH ALL_KEYS_IN_TABLE (CONSTRAINT_NAME,CONSTRAINT_TYPE,PARENT_TABLE_NAME,PARENT_COL_NAME,PARENT_COL_NAME_DATA_TYPE,REFERENCE_TABLE_NAME,REFERENCE_COL_NA...
Possible Loss of Fraction
...two int's into a floating point value the fraction portion is lost. If you cast one of the items to a float, you won't get this error.
So for example turn 10 into a 10.0
double returnValue = (myObject.Value / 10.0);
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Execute Insert command and return inserted Id in Sql
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I was getting an invalid cast error when trying to cast the int modified = (int)cmd.ExecuteScalar(); to an int. I had to use Convert to convert it to an int. int modified = Convert.ToInt32(cmd.ExecuteScalar());
– Baddack
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What are all the common undefined behaviours that a C++ programmer should know about? [closed]
...ts in the number (e.g. int64_t i = 1; i <<= 72 is undefined)
Types, Cast and Const
Casting a numeric value into a value that can't be represented by the target type (either directly or via static_cast)
Using an automatic variable before it has been definitely assigned (e.g., int i; i++; cout...
Pointer arithmetic for void pointer in C
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cast it to a char pointer an increment your pointer forward x bytes ahead.
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What is std::move(), and when should it be used?
...the object has type "rvalue-reference" (Type &&).
std::move() is a cast that produces an rvalue-reference to an object, to enable moving from it.
It's a new C++ way to avoid copies. For example, using a move constructor, a std::vector could just copy its internal pointer to data to the new...