We have already seen in this chapter how enums can be somewhat tricky to handle. Thankfully, we can use match on an enum:

enum MyFirstEnum 
{ 
    TupleType(f32, i8, String), 
    StructType {varone: i32, vartwo: f64}, 
    NewTypeTuple(i32), 
    SomeVarName 
} 
fn tuple_type(v: f32, c: i8, st: String) {//code} 
fn struct_type(v1: i32, v2: f64) {//code} 
fn new_type_tuple(n: i32) {//code} 
fn process_varname() {//code}  
 
fn match_enum_code(e: MyFirstEnum) 
{ 
match e { 
   MyFirstEnum::SomeVarName => process_varname(), 
   MyFirstEnum::TupleType(f,i,s) => tuple_type(f,i,s), 
   MyFirstEnum::StructType(v1,v2) => struct_type(v1,v2), 
   MyFirstEnum::NewTypeTuple(i) => new_type_tuple(i) 
}; 
} 

You will notice that in this example, _ is not included. That's because we explicitly match against all the possible choices of the enum, so we don't need a catch-all case. If, for instance, we missed NewTypeTuple, the code would need to include a catch-all:

fn match_enum_code(e:MyFirstEnum) 
{ 
match e { 
   MyFirstEnum::SomeVarName => process_varname(), 
   MyFirstEnum::TupleType(f,i,s) => tuple_type(f,i,s), 
   MyFirstEnum::StructType(v1,v2) => struct_type(v1,v2), 
   _ => return  // breaks out of the match 
}; 
}