Interpreter - Initial environment implementation
This commit is contained in:
parent
7f94906412
commit
8b44af08ba
1 changed files with 29 additions and 0 deletions
|
@ -0,0 +1,29 @@
|
||||||
|
use std::collections::HashMap;
|
||||||
|
|
||||||
|
use crate::{errors::InterpreterError, tokens::Token};
|
||||||
|
|
||||||
|
use super::Value;
|
||||||
|
|
||||||
|
/// The execution environment.
|
||||||
|
#[derive(Debug, Default)]
|
||||||
|
pub struct Environment {
|
||||||
|
values: HashMap<String, Value>,
|
||||||
|
}
|
||||||
|
|
||||||
|
impl Environment {
|
||||||
|
/// Define a new variable.
|
||||||
|
pub fn define(&mut self, name: String, value: Value) {
|
||||||
|
self.values.insert(name, value);
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Get the value of a variable.
|
||||||
|
pub fn get(&self, name: &Token) -> Result<Value, InterpreterError> {
|
||||||
|
match self.values.get(&name.lexeme as &str) {
|
||||||
|
None => Err(InterpreterError::new(
|
||||||
|
name,
|
||||||
|
&format!("undefined variable '{}'", name.lexeme),
|
||||||
|
)),
|
||||||
|
Some(value) => Ok(value.clone()),
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
Loading…
Reference in a new issue