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Why does C++ not allow inherited friendship?
...swers), but the lack of something along the lines of virtual friend class Foo; puzzles me. Does anyone know the historical background behind this decision? Was friendship really just a limited hack that has since found its way into a few obscure respectable uses?
...
PostgreSQL: How to pass parameters from command line?
... statement, use apostrophes around variable name, like this: SELECT * FROM foo WHERE bar = :'v3';
– Cromax
Feb 8 '17 at 7:04
1
...
How do Mockito matchers work?
... generally used in assertions such as the one below.
/* Mockito */ verify(foo).setPowerLevel(gt(9000));
/* Hamcrest */ assertThat(foo.getPowerLevel(), is(greaterThan(9000)));
Mockito matchers exist, separate from Hamcrest-style matchers, so that descriptions of matching expressions fit directly in...
What is the difference between `raise “foo”` and `raise Exception.new(“foo”)`?
...
Technically, the first raises a RuntimeError with the message set to "foo", and the second raises an Exception with the message set to "foo".
Practically, there is a significant difference between when you would want to use the former and when you want to use the latter.
Simply put, you prob...
Why no ICloneable?
... with cloning comes with a variation of the "diamond problem": if CloneableFoo inherits from [not publicly cloneable] Foo, should CloneableDerivedFoo derive from...
– supercat
Aug 10 '12 at 15:26
...
Why should we typedef a struct so often in C?
...position of ordering relationships among header files.
Consider:
#ifndef FOO_H
#define FOO_H 1
#define FOO_DEF (0xDEADBABE)
struct bar; /* forward declaration, defined in bar.h*/
struct foo {
struct bar *bar;
};
#endif
With such a definition, not using typedefs, it is possible for a compil...
Why does calling a method in my derived class call the base class method?
...e two keywords in a long inheritance chain. Consider the following:
class Foo { public virtual void DoFoo() { Console.WriteLine("Foo"); } }
class Bar:Foo { public override sealed void DoFoo() { Console.WriteLine("Bar"); } }
class Baz:Bar { public virtual void DoFoo() { Console.WriteLine("Baz"); } }...
Use of “global” keyword in Python
... you want to modify them you have to use the global keyword. For example:
foo = 1
def test():
foo = 2 # new local foo
def blub():
global foo
foo = 3 # changes the value of the global foo
In your case, you're just accessing the list sub.
...
Is it possible to “await yield return DoSomethingAsync()”
...it has to wait for that operation to finish.
async Task<IEnumerable<Foo>> Method(String [] Strs)
{
foreach(var str in strs)
{
yield return await DoSomethingAsync( str)
}
}
The awaiting Method mixes meanings. Do you want to wait until the Task has an IEnumerable and then bl...
How to display pandas DataFrame of floats using a format string for columns?
...aFrame([123.4567, 234.5678, 345.6789, 456.7890],
index=['foo','bar','baz','quux'],
columns=['cost'])
print(df)
yields
cost
foo $123.46
bar $234.57
baz $345.68
quux $456.79
but this only works if you want every float to be formatted with a dollar si...