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#[macro_export]
macro_rules! lets {
(
let $expect:pat = $result:expr;
else $failure:expr;
lift $success:expr;
) => {
match $result {
$expect => $success,
_ => $failure,
}
};
(
$(let $expect:pat = $result:expr;)+
lift $success:expr;
) => {
lets! {
$(let $expect = $result;)*
else ();
lift $success;
}
};
(
$(let $expect:pat = $result:expr;)+
else $failure:expr;
) => {
lets! {
$(let $expect = $result;)*
else $failure;
lift ();
}
};
(
$(let $expect:pat = $result:expr;)+
) => {
lets! {
$(let $expect = $result;)*
else ();
lift ();
}
};
(
let $expect_first:pat = $result_first:expr;
$(let $expect_next:pat = $result_next:expr;)+
else $failure:expr;
lift $success:expr;
) => {
match $result_first {
$expect_first => lets! {
$(let $expect_next = $result_next;)*
else $failure;
lift $success;
},
_ => $failure,
}
};
}