Struct Env 

pub struct Env { /* private fields */ }

The names a running program can reach: the values it has assigned, the verbs it has named, and the arguments bound to its parameters.

An explicit definition runs with a frame of its own on top: J’s =. writes there and =: writes to the globals, and a name is looked for in the frame before the globals. Frames do not nest — a definition called from another sees only its own locals, which is what both references do.

Implementations

impl Env

pub fn new(args: Vec<Array>) -> Env

pub fn get(&self, name: &str) -> Option<Array>

pub fn assign(&mut self, name: String, value: Array, scope: Scope)

pub fn define(&mut self, name: String, verb: Verb)

pub fn global(&self, name: &str) -> Option<Array>

A global by name, reached past any frame. An operator’s array operand lives here for as long as its body runs, so that the body’s own frame does not hide it.

pub fn set_global(&mut self, name: String, value: Array)

pub fn unset_global(&mut self, name: &str)

pub fn undefine(&mut self, name: &str)

pub fn verb(&self, name: &str) -> Option<&Verb>

pub fn arg(&self, i: usize) -> Result<Array>

pub fn enter( &mut self, frame: HashMap<String, Array>, def: Arc<ExplicitDef>, span: Span, ) -> Result<()>

Start a definition’s frame. Fails rather than overflowing the stack.

pub fn leave(&mut self) -> HashMap<String, Array>

End a definition’s frame and hand back the names it assigned.

pub fn current_def(&self) -> Option<Arc<ExplicitDef>>

The innermost definition now running; $: and ∇ name it.