BOOST_OUTCOME_TRYV(expr)/BOOST_OUTCOME_TRY(expr)
Evaluate an expression which results in a type matching the following customisation points, continuing execution if successful, immediately returning try_operation_return_as(X)
from the calling function if unsuccessful:
BOOST_OUTCOME_V2_NAMESPACE::
try_operation_has_value(X)
BOOST_OUTCOME_V2_NAMESPACE::
try_operation_return_as(X)
BOOST_OUTCOME_V2_NAMESPACE::
try_operation_extract_value(X)
Default overloads for these customisation points are provided. See the recipe for supporting foreign input to BOOST_OUTCOME_TRY
.
The difference between the BOOST_OUTCOME_TRYV(expr)
and BOOST_OUTCOME_TRY(expr)
editions is that the latter will set a variable if two or more macro arguments are present (see BOOST_OUTCOME_TRY(var, expr)
). The former requires the T
to be void
.
Hints are given to the compiler that the expression will be successful. If you expect failure, you should use BOOST_OUTCOME_TRYV_FAILURE_LIKELY(expr)
instead.
Overridable: Not overridable.
Definition: Firstly the expression’s temporary is bound to a uniquely named, stack allocated, auto &&
. If that reference’s bound object’s try_operation_has_value()
is false, immediately execute return try_operation_return_as(propagated unique reference);
, propagating the rvalue/lvalue/etc-ness of the original expression.
Header: <boost/outcome/try.hpp>