26 lines
669 B
Rust
26 lines
669 B
Rust
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use parser::AST;
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use parser::AST::*;
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pub fn evaluate(ast: AST) -> String {
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match reduce(ast) {
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None => return "error".to_string(),
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Some(DoNothing) => "".to_string(),
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Some(Number(n)) => return format!("{}", n),
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Some(LangString(s)) => return format!("\"{}\"", s),
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_ => return "not implemented".to_string()
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}
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}
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fn reduce(ast: AST) -> Option<AST> {
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match ast {
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Statements(stmts) => {
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let mut reduction = Some(DoNothing);
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for stmt in stmts.into_iter() {
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reduction = reduce(stmt);
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}
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reduction
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},
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other_ast => Some(other_ast)
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}
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}
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