Struct TopLevel 

pub struct TopLevel {
    pub env: Env,
    pub names: Vec<SmolStr>,
    pub ctx: EvalCtx,
}

Accumulated evaluator state: environment vector and staging context. Exists purely as a convenience for multi-expression REPL sessions.

Fields

env: Env

The base runtime environment. The floor has no top-level define, so ordinary evaluation never extends this — every form is closed, and only ctx carries state between forms. It exists so an embedding can pre-seed bindings: slot i holds the value of names[i], and lowering resolves free names against names positionally.

names: Vec<SmolStr>

Surface names for the slots of env, in lockstep.

ctx: EvalCtx

The staging context: fresh-variable counter, ANF block stack, closure memo table, tower level, and the I/O implementation.

Implementations

impl TopLevel

pub fn new() -> Self

Construct over a real terminal (TerminalIo).

Panics when no terminal is available, so tests and other non-interactive embeddings must use with_io with a HeadlessIo instead.

pub fn with_io(io: Box<dyn NarjuIo>) -> Self

Construct with an explicit I/O implementation.

Use this in tests to avoid depending on a real terminal:

use narju::io::headless::HeadlessIo;
use narju::repl::TopLevel;

let mut top = TopLevel::with_io(Box::new(HeadlessIo::empty()));
assert_eq!(top.eval_int("(+ 1 2)"), 3);

pub fn eval_exp(&mut self, sexp: &Sexp) -> Result<Val, NarjuError>

Evaluate a single expression in the current environment.

pub fn run_str(&mut self, src: &str) -> Result<Vec<RunResult>, NarjuError>

Parse and evaluate all forms in src, returning each result.

pub fn run_file(&mut self, path: &str) -> Result<Vec<RunResult>, NarjuError>

Parse and evaluate a file.

pub fn eval(&mut self, src: &str) -> Val

Evaluate a source string, panicking on error. For tests only.

pub fn eval_int(&mut self, src: &str) -> i64

Evaluate and unwrap as i64, panicking on type mismatch. For tests only.

Trait Implementations

impl Default for TopLevel

fn default() -> Self

Returns the “default value” for a type.