31 lines
514 B
Rust
31 lines
514 B
Rust
use tokenizer::Token;
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/* grammar
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expr : term ((PLUS|MIMUS) term)*
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term : factor ((MUL | DIV) factor)*
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factor : NUM | LPAREN expr RPAREN
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*/
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#[derive(Debug)]
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enum AST {
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BinOp(Box<AST>, Box<AST>, Box<AST>),
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Number(f64),
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Name(String),
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}
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#[derive(Debug)]
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pub struct ParseError {
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err: String
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}
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pub type ParseResult = Result<AST, ParseError>;
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pub fn parse(input: Vec<Token>) -> ParseResult {
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let mut current_token: Token;
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return Err(ParseError { err: "error!".to_string() });
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}
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