Module ketos::exec

Implements a virtual machine which interprets bytecode functions.

The virtual machine consists of:

• A value stack, containing values stored or passed into functions
• A single value register into which values can be loaded from the stack and from which values can be pushed onto the stack.
• A call stack, containing for each successive function:
  • an index into the bytecode ("instruction pointer")
  • an index into the value stack ("stack pointer")
  • any constant values referenced by bytecode instructions
  • any enclosed values referenced by bytecode instructions

Bytecode instructions may modify or consume the value register, push values onto the stack, modify the instruction pointer, add a function call to the call stack, or return from the function currently being executed.

When a bytecode function is added to the stack, its stack pointer will be set to the position of the first argument which is passed to the function. It may load or modify these values. When the function returns, all values after the stack pointer will be automatically removed from the stack before returning control to the previous function execution. Every function returns a value, which is available to the calling function through the value register.

Structs

Context

Represents an execution context

Enums

ExecError

Represents an error generated while executing bytecode.

Functions

call_function	Calls a function or lambda in the given scope with the given arguments.
execute	Executes a code object and returns the value.
execute_function	Executes a Function in the given scope and returns the value.
execute_lambda	Executes a Lambda in the given scope and returns the value.
panic	Returns a Panic error with the given value.
panic_none	Returns a Panic error with no value.