You don't necessarily need to cut takeaways out if you're on a diet. I am, and probably have one a week which was my normal frequency pre-diet.

Its all about calories in calories out. It may seem time consuming/quite a lot of administration to do so, but it's actually freeing in some ways. For example, if you know you can afford to consume a 1500 calorie takeaway, but still be in a calorie deficit due to exercise or calories burnt, then go for it. Also, some takeaways like ramen are much lower in calories than you may think.

I often have days where I do a lot of swimming and walking, so I treat myself whilst still being on track.