How to get argument of a variant? - rust

Question

Having these enums
pub enum Symbol {
X,
O,
}
pub enum CellContent {
Move(Symbol),
Empty,
}
and
let cell_content = CellContent::Move(Symbol::X);
how can I get the Symbol ? Of course if it's of variant Move(Symbol)
This doesn't work
if cell_0_0 == Move(a_symbol) {
return Some(a_symbol);
}
I cannot also do the following because I must do nothing (code must continue evaluation); and the following doesn't even compile at all !
match cell_0_0 {
Move(symbol) => return symbol;
_ => // do nothing;
}
// code must go on to check further conditions
| I still have some problem with basic syntax of rust, so I'm experiencing making some basic programs
So question is
How to
check if my variable is a variant of Move(Symbol)
if yes return (a copy of) symbol
else do nothing, so code can go on and do more checks
?
Edit 1: Full (not working) code
pub fn some_one_win(&self) -> Option<Symbol> {
let cell_0_0: CellContent = self.table[0][0];
let cell_0_1: CellContent = self.table[0][1];
let cell_0_2: CellContent = self.table[0][2];
if cell_0_0 == cell_0_1 && cell_0_0 == cell_0_2 {
match cell_0_0 {
Move(symbol) => return symbol;
_ => // how to 'do nothing' here ?;
}
}
let cell_1_0: CellContent = self.table[1][0];
let cell_1_1: CellContent = self.table[1][1];
let cell_1_2: CellContent = self.table[1][2];
if cell_1_0 == cell_1_1 && cell_1_0 == cell_1_2 {
match cell_1_0 {
Move(symbol) => return symbol;
_ => // how to 'do nothing' here ?;
}
}
... and so on ..
}

Answer 1

I cannot also do the following because I must do nothing (code must continue evaluation); and the following doesn't even compile at all !
match cell_0_0 {
Move(symbol) => return symbol;
_ => // do nothing;
}
You can do that, if you get the syntax right:
match cell_0_0 {
CellContent::Move(symbol) => {
return Some(symbol);
}
_ => {} // do nothing
}
But as PitaJ mentioned, when there’s only one pattern plus _, the if let construct is usually a cleaner alternative:
if let CellContent::Move(symbol) = cell_0_0 {
return Some(symbol);
}