use std::{cell::RefCell, path::PathBuf, rc::Rc}; use crate::{ builtins::global_builtins, errors::{Error, ErrorKind, EvalResult}, nix_search_path::NixSearchPath, observer::{DisassemblingObserver, NoOpObserver, TracingObserver}, value::Value, SourceCode, }; /// Runtime options for the Tvix interpreter #[derive(Debug, Clone, Default)] #[cfg_attr(feature = "repl", derive(clap::Parser))] pub struct Options { /// Dump the raw AST to stdout before interpreting #[cfg_attr(feature = "repl", clap(long, env = "TVIX_DISPLAY_AST"))] display_ast: bool, /// Dump the bytecode to stdout before evaluating #[cfg_attr(feature = "repl", clap(long, env = "TVIX_DUMP_BYTECODE"))] dump_bytecode: bool, /// Trace the runtime of the VM #[cfg_attr(feature = "repl", clap(long, env = "TVIX_TRACE_RUNTIME"))] trace_runtime: bool, /// A colon-separated list of directories to use to resolve `<...>`-style paths #[cfg_attr(feature = "repl", clap(long, short = 'I', env = "NIX_PATH"))] nix_search_path: Option, } pub fn interpret(code: &str, location: Option, options: Options) -> EvalResult { let source = SourceCode::new(); let file = source.add_file( location .as_ref() .map(|p| p.to_string_lossy().to_string()) .unwrap_or_else(|| "[tvix-repl]".into()), code.into(), ); let parsed = rnix::ast::Root::parse(code); let errors = parsed.errors(); if !errors.is_empty() { let err = Error { kind: ErrorKind::ParseErrors(errors.to_vec()), span: file.span, }; err.fancy_format_stderr(&source); return Err(err); } // If we've reached this point, there are no errors. let root_expr = parsed .tree() .expr() .expect("expression should exist if no errors occured"); if options.display_ast { println!("{:?}", root_expr); } // TODO: encapsulate this import weirdness in builtins let builtins = Rc::new(RefCell::new(global_builtins())); #[cfg(feature = "impure")] { // We need to insert import into the builtins, but the // builtins passed to import must have import *in it*. let import = Value::Builtin(crate::builtins::impure::builtins_import( builtins.clone(), source.clone(), )); builtins.borrow_mut().insert("import", import); // TODO: also add it into the inner builtins set }; let result = if options.dump_bytecode { crate::compiler::compile( &root_expr, location, file.clone(), builtins, &mut DisassemblingObserver::new(source.clone(), std::io::stderr()), ) } else { crate::compiler::compile( &root_expr, location, file.clone(), builtins, &mut NoOpObserver::default(), ) }?; for warning in result.warnings { warning.fancy_format_stderr(&source); } for error in &result.errors { error.fancy_format_stderr(&source); } if let Some(err) = result.errors.last() { return Err(err.clone()); } let result = if options.trace_runtime { crate::vm::run_lambda( options.nix_search_path.unwrap_or_default(), &mut TracingObserver::new(std::io::stderr()), result.lambda, ) } else { crate::vm::run_lambda( options.nix_search_path.unwrap_or_default(), &mut NoOpObserver::default(), result.lambda, ) }; if let Err(err) = &result { err.fancy_format_stderr(&source); } result.map(|r| { for warning in r.warnings { warning.fancy_format_stderr(&source); } r.value }) }