35 lines
843 B
Rust
35 lines
843 B
Rust
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use std::collections::HashMap;
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use tt::SmolStr;
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// Identifier for an interned symbol.
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#[derive(Hash, Eq, PartialEq, Copy, Clone)]
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pub struct Symbol(u32);
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#[derive(Default)]
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struct IdentInterner {
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idents: HashMap<SmolStr, u32>,
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ident_data: Vec<SmolStr>,
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}
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impl IdentInterner {
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fn intern(&mut self, data: &str) -> Symbol {
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if let Some(index) = self.idents.get(data) {
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return *index;
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}
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let index = self.idents.len() as u32;
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self.ident_data.push(data.clone());
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self.idents.insert(data.clone(), index);
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index
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}
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fn get(&self, index: u32) -> &SmolStr {
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&self.ident_data[index as usize]
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}
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#[allow(unused)]
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fn get_mut(&mut self, index: u32) -> &mut SmolStr {
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self.ident_data.get_mut(index as usize).expect("Should be consistent")
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}
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}
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