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use std::str;
#[derive(Debug)]
struct Token {
kind: String,
val: String,
}
fn main() {
let input: &str = "2y + 11 ^ x";
let input = input.replace(" ", "");
println!("{}", input);
let mut num_vec: String = String::new();
let mut char_vec: String = String::new();
let mut result: Vec<Token> = vec![];
for letter in input.chars() {
if letter.is_digit(10) {
num_vec.push(letter);
} else if letter == '.' {
num_vec.push(letter);
} else if letter.is_alphabetic() {
let literal = buffer_to_token("Literal", &num_vec[..]);
if let Some(x) = literal {
result.push(x);
}
char_vec.push(letter);
num_vec.clear();
} else if is_operator(letter) {
let literal = buffer_to_token("Literal", &num_vec[..]);
let variable = buffer_to_token("Variable", &char_vec[..]);
if let Some(x) = literal {
result.push(x);
}
if let Some(x) = variable {
result.push(x);
}
num_vec.clear();
char_vec.clear();
result.push(Token { kind: "Operator".into(), val: letter.to_string() });
}
println!("{}", letter);
for token in &result {
println!("{:?}", token);
}
}
}
fn buffer_to_token(k: &str, v: &str) -> Option<Token> {
if v.len() > 0 {
let token = Token {
kind: k.into(),
val: v.chars().collect::<String>()
};
Some(token)
} else {
None
}
}
fn is_operator(x: char) -> bool {
match x {
'+' | '-' | '/' | '*' | '^' => true,
_ => false
}
}
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