Enum MatchingMode 

enum MatchingMode {
    Check,
    Bind,
    Assign,
}

We need to do pattern matching in two phases: One to check if the pattern matches, and one to fill the bindings of patterns. This is necessary to prevent double moves and similar problems. For example:

struct X;
match (X, 3) {
    (b, 2) | (b, 3) => {},
    _ => {}
}

If we do everything in one pass, we will move X to the first b, then we see that the second field of tuple doesn’t match and we should move the X to the second b (which here is the same thing, but doesn’t need to be) and it might even doesn’t match the second pattern and we may want to not move X at all.

Variants

Check

Check that if this pattern matches

Bind

Assume that this pattern matches, fill bindings

Assign

Assume that this pattern matches, assign to existing variables.

Trait Implementations

impl Clone for MatchingMode

fn clone(&self) -> MatchingMode

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MatchingMode

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for MatchingMode

fn eq(&self, other: &MatchingMode) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for MatchingMode

impl Eq for MatchingMode

impl StructuralPartialEq for MatchingMode