var curve : AnimationCurve = AnimationCurve.Linear (0, 0, 5, 5);
// Extract the time from the first keyframe of a curve
Debug.Log(curve[0].time);

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
public AnimationCurve curve = AnimationCurve.Linear(0, 0, 5, 5);
void Awake() {
Debug.Log(curve[0].time);
}
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

public curve as AnimationCurve = AnimationCurve.Linear(0, 0, 5, 5)

def Awake():
Debug.Log(curve[0].time)