Struct Evaluator 

pub struct Evaluator {
    pub env: Environment,
    pub gas: u64,
    pub gas_limit: u64,
    pub log_output: Vec<String>,
    pub action_names: Vec<String>,
    pub mock_responses: Vec<(String, String, Value)>,
}

The core evaluator — walks AST nodes and produces Values.

Fields

env: Environment

Variable environment (scoped).

gas: u64

Gas counter — limits total steps to prevent infinite loops.

gas_limit: u64

Gas limit.

log_output: Vec<String>

Captured log output from core.log.

action_names: Vec<String>

Action names registered in the space (for resolving action references).

mock_responses: Vec<(String, String, Value)>

Mock capability responses (module, function) → response Value. Used by the test runner for with_responses blocks.

Implementations

impl Evaluator

pub fn new(gas_limit: u64) -> Self

Create a new evaluator with the given gas limit.

pub fn eval_expr(&mut self, expr: &Expr) -> EvalResult<Value>

Evaluate an expression to a Value.

pub fn eval_qualified_call( &mut self, module: &str, function: &str, args: &[Expr], ) -> EvalResult<Value>

Evaluate a qualified call: module.function(args).

pub fn eval_if_expr(&mut self, if_expr: &IfExpr) -> EvalResult<Value>

pub fn eval_lambda(&mut self, lambda: &LambdaExpr) -> EvalResult<Value>

pub fn eval_block(&mut self, block: &Block) -> EvalResult<Value>

Execute a block of statements. Returns the value of the last expression, or Nil.

pub fn eval_stmt(&mut self, stmt: &Stmt) -> EvalResult<Value>

Execute a single statement.

pub fn call_stdlib( &mut self, module: &str, function: &str, args: Vec<Value>, ) -> EvalResult<Value>

Call a stdlib function by module and function name.

pub fn structural_eq(&self, a: &Value, b: &Value) -> bool

Deep structural equality. NaN != NaN. Functions always false.

pub fn value_to_display_string(&self, val: &Value) -> String

Convert a Value to its display string (for string interpolation, core.log, etc.)

pub fn string_comparison(&self, _a: &str, _b: &str) -> Ordering

String comparison for ordering (used by string comparison operators). Note: PEPL spec says string comparison compares by length, not lexicographic. This matches the eval_comparison implementation.