85 lines
2.1 KiB
Rust
85 lines
2.1 KiB
Rust
//! Garbage-collecting context for variables.
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use std::collections::HashMap;
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use crate::{Identifier, Type, Value};
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/// Garbage-collecting context for variables.
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#[derive(Debug, Clone)]
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pub struct Context {
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pub variables: HashMap<Identifier, (VariableData, UsageData)>,
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}
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impl Context {
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pub fn new() -> Self {
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Self {
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variables: HashMap::new(),
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}
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}
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pub fn contains(&self, identifier: &Identifier) -> bool {
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self.variables.contains_key(identifier)
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}
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pub fn get(&self, identifier: &Identifier) -> Option<&(VariableData, UsageData)> {
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self.variables.get(identifier)
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}
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pub fn get_type(&self, identifier: &Identifier) -> Option<&Type> {
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match self.variables.get(identifier) {
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Some((VariableData::Type(r#type), _)) => Some(r#type),
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_ => None,
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}
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}
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pub fn get_value(&self, identifier: &Identifier) -> Option<&Value> {
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match self.variables.get(identifier) {
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Some((VariableData::Value(value), _)) => Some(value),
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_ => None,
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}
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}
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pub fn get_variable_data(&self, identifier: &Identifier) -> Option<&VariableData> {
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match self.variables.get(identifier) {
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Some((variable_data, _)) => Some(variable_data),
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_ => None,
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}
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}
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pub fn set_type(&mut self, identifier: Identifier, r#type: Type) {
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self.variables.insert(
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identifier,
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(VariableData::Type(r#type), UsageData::default()),
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);
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}
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pub fn set_value(&mut self, identifier: Identifier, value: Value) {
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self.variables.insert(
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identifier,
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(VariableData::Value(value), UsageData::default()),
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);
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}
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pub fn collect_garbage(&mut self) {
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self.variables
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.retain(|_, (_, usage_data)| usage_data.used < usage_data.allowed_uses);
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}
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}
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impl Default for Context {
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fn default() -> Self {
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Self::new()
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}
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}
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#[derive(Debug, Clone)]
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pub enum VariableData {
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Value(Value),
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Type(Type),
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}
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#[derive(Default, Debug, Clone)]
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pub struct UsageData {
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pub allowed_uses: u16,
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pub used: u16,
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}
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