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mod input;
pub mod ui;
#[derive(Default)]
pub struct Calculator {
stack: Vec<f64>,
input_buffer: String,
}
impl Calculator {
fn push_buffer_to_stack(&mut self) {
self.stack.push(self.input_buffer.parse::<f64>().unwrap());
self.input_buffer = String::new();
}
fn perform_operation(&mut self, op: Operator) {
let rhs = match self.stack.pop() {
Some(f) => f,
None => {
return;
}
};
let lhs = match self.stack.pop() {
Some(f) => f,
None => {
return;
}
};
match op {
Operator::Add => self.stack.push(lhs + rhs),
Operator::Sub => self.stack.push(lhs - rhs),
Operator::Mul => self.stack.push(lhs * rhs),
Operator::Div => self.stack.push(lhs / rhs),
}
}
}
pub enum Operator {
Add,
Sub,
Mul,
Div,
}
impl Operator {
pub fn parse(c: char) -> Result<Self, ParseOperatorError> {
match c {
'+' => Ok(Self::Add),
'-' => Ok(Self::Sub),
'*' => Ok(Self::Mul),
'/' => Ok(Self::Div),
_ => Err(ParseOperatorError(c)),
}
}
}
pub struct ParseOperatorError(char);
pub enum Signal {
None,
Exit,
}
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