// Package expr provides the abstract Expression interface for all evaluatable
// expression types in the lambda runtime.
package expr

import (
	"fmt"
)

// Expression is the base interface for all evaluatable expression types.
// Different evaluation modes (lambda calculus, SKI combinators, typed lambda
// calculus, etc.) implement this interface with their own concrete types.
type Expression interface {
	// The expression should have a human-readable representation.
	fmt.Stringer
}