2022-09-06 13:52:29 +00:00
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use std::{cell::RefCell, rc::Rc};
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2022-09-09 20:08:40 +00:00
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use crate::{value::Value, lexer::Lexer, parser::Parser, eval::{Environment, eval_stmt, eval_expr, EnvRef}, expr::Stmt, stdlib};
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2022-09-06 13:52:29 +00:00
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2022-09-09 20:08:40 +00:00
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pub fn interpret(src: &str, fname: Option<String>, env: Option<EnvRef>, repl: bool) -> Result<Value, Box<dyn std::error::Error>> {
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2022-09-07 20:11:51 +00:00
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let mut lexer = Lexer::new(src, fname);
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2022-09-06 13:52:29 +00:00
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lexer.lex()?;
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2022-09-07 20:11:51 +00:00
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let mut parser = Parser::new(lexer.into_tokens(), repl);
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2022-09-06 13:52:29 +00:00
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let ast = parser.parse()?;
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let environ;
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if let Some(env) = env {
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environ = env;
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} else {
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2022-09-09 20:08:40 +00:00
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environ = Rc::new(RefCell::new(Environment::new()));
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stdlib::load(&mut environ.borrow_mut());
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2022-09-06 13:52:29 +00:00
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}
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2022-09-09 20:08:40 +00:00
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2022-09-06 13:52:29 +00:00
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let mut result = Value::Nil;
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for stmt in ast {
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if let Stmt::Expr{expr} = stmt {
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result = eval_expr(&expr, environ.clone())?;
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} else {
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eval_stmt(&stmt, environ.clone())?;
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result = Value::Nil;
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}
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}
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Ok(result)
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}
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