Python has an interesting for statement which lets you specify an else clause.
for
else
In a construct like this one:
for i in foo: if
A simpler way to express your actual logic is with std::none_of:
if (std::none_of(std::begin(foo), std::end(foo), bar)) baz();
If the range proposal for C++17 gets accepted, hopefully this will simplify to:
if (std::none_of(foo, bar)) baz();