Struct endbasic_core::exec::Machine

pub struct Machine { /* fields omitted */ }

Executes an EndBASIC program and tracks its state.

Implementations

impl Machine

pub fn add_clearable(&mut self, clearable: Box<dyn Clearable>)

Registers the given clearable.

In the common case, functions and commands hold a reference to the out-of-machine state they interact with. This state is invisible from here, but we may need to have access to it to reset it as part of the clear operation. In those cases, such state must be registered via this hook.

pub fn add_command(&mut self, command: Rc<dyn Command>)

Registers the given builtin command, which must not yet be registered.

pub fn add_function(&mut self, function: Rc<dyn Function>)

Registers the given builtin function, which must not yet be registered.

pub fn clear(&mut self)

Resets the state of the machine by clearing all variable.

pub fn exit(&mut self, code: u8)

Tells the machine to stop execution at the next statement boundary.

The exec() call that’s stopped by this invocation will return the code given to this call.

pub fn get_symbols(&self) -> &Symbols

Obtains immutable access to the state of the symbols.

pub fn get_mut_symbols(&mut self) -> &mut Symbols

Obtains mutable access to the state of the symbols.

pub fn get_var_as_bool(&self, name: &str) -> Result<bool>

Retrieves the variable name as a boolean. Fails if it is some other type or if it’s not defined.

pub fn get_var_as_int(&self, name: &str) -> Result<i32>

Retrieves the variable name as an integer. Fails if it is some other type or if it’s not defined.

pub fn get_var_as_string(&self, name: &str) -> Result<&str>

Retrieves the variable name as a string. Fails if it is some other type or if it’s not defined.

pub async fn dim_array(
    &mut self,
    name: &str,
    subtype: &VarType,
    dimensions: &[Expr]
) -> Result<()>

Defines a new array name of type subtype with dimensions. The array must not yet exist, and the name may not overlap function or variable names.

pub async fn exec(&mut self, input: &mut dyn Read) -> Result<StopReason>

Executes a program extracted from the input readable.

Note that this does not consume self. As a result, it is possible to execute multiple different programs on the same machine, all sharing state.

Trait Implementations

impl Default for Machine

fn default() -> Machine

Returns the “default value” for a type.