use ergotree_ir::mir::select_field::SelectField;
use ergotree_ir::mir::value::Value;
use crate::eval::env::Env;
use crate::eval::EvalContext;
use crate::eval::EvalError;
use crate::eval::Evaluable;
impl Evaluable for SelectField {
fn eval(&self, env: &Env, ctx: &mut EvalContext) -> Result<Value, EvalError> {
let input_v = self.input.eval(env, ctx)?;
match input_v {
Value::Tup(items) => items
.get(self.field_index.zero_based_index())
.cloned()
.ok_or_else(|| {
EvalError::NotFound(format!(
"SelectField field index is out of bounds. Index: {0:?}, tuple: {1:?}",
self.field_index, items
))
}),
_ => Err(EvalError::UnexpectedValue(format!(
"expected SelectField input to be Value::Tup, got: {0:?}",
input_v
))),
}
}
}