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What does auto&& tell us?
...n invalid state.
Now let's apply this to the case of auto&& var = foo();, as given in your question, where foo returns a T by value. In this case we know for sure that the type of var will be deduced as T&&. Since we know for certain that it's an rvalue, we don't need std::forward's...
How can I iterate over an enum?
...
The typical way is as follows:
enum Foo {
One,
Two,
Three,
Last
};
for ( int fooInt = One; fooInt != Last; fooInt++ )
{
Foo foo = static_cast<Foo>(fooInt);
// ...
}
Please note, the enum Last is meant to be skipped by the iteration. Utili...
Does Typescript support the ?. operator? (And, what's it called?)
...
Not as nice as a single ?, but it works:
var thing = foo && foo.bar || null;
You can use as many && as you like:
var thing = foo && foo.bar && foo.bar.check && foo.bar.check.x || null;
...
How does having a dynamic variable affect performance?
...
void M()
{
dynamic d1 = whatever;
dynamic d2 = d1.Foo();
then the compiler will generate code that is morally like this. (The actual code is quite a bit more complex; this is simplified for presentation purposes.)
class C
{
static DynamicCallSite FooCallSite;
void...
How to take column-slices of dataframe in pandas
...ement.
Let's assume we have a DataFrame with the following columns:
foo, bar, quz, ant, cat, sat, dat.
# selects all rows and all columns beginning at 'foo' up to and including 'sat'
df.loc[:, 'foo':'sat']
# foo bar quz ant cat sat
.loc accepts the same slice notation that Python lists do...
Store boolean value in SQLite
...alse and true. You could declare the column type like this:
CREATE TABLE foo(mycolumn BOOLEAN NOT NULL CHECK (mycolumn IN (0,1)));
Omit the NOT NULL if you want to allow NULL in addition to 0 and 1.
The use of the type name BOOLEAN here is for readability, to SQLite it's just a type with NUMERI...
How to use CMAKE_INSTALL_PREFIX
...ists.txt
cmake_minimum_required (VERSION 2.8)
set (CMAKE_INSTALL_PREFIX /foo/bar/bubba)
message("CIP = ${CMAKE_INSTALL_PREFIX} (should be /foo/bar/bubba")
project (BarkBark)
message("CIP = ${CMAKE_INSTALL_PREFIX} (should be /foo/bar/bubba")
set (CMAKE_INSTALL_PREFIX /foo/bar/bubba)
message("CIP = ...
How to replace a string in multiple files in linux command line
...
cd /path/to/your/folder
sed -i 's/foo/bar/g' *
Occurrences of "foo" will be replaced with "bar".
On BSD systems like macOS, you need to provide a backup extension like -i '.bak' or else "risk corruption or partial content" per the manpage.
cd /path/to/you...
Express-js wildcard routing to cover everything under and including a path
I'm trying to have one route cover everything under /foo including /foo itself. I've tried using /foo* which work for everything except it doesn't match /foo . Observe:
...
How to get next/previous record in MySQL?
...
next:
select * from foo where id = (select min(id) from foo where id > 4)
previous:
select * from foo where id = (select max(id) from foo where id < 4)
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