What edition are we talking? Because I've never done 4th and it's been a looooong time since I did first or second. So based on that I'll give you the 3rd Edition answer.

The Priest/Cleric can cast a resurrection. I believe it's a 7th or 8th level spell; or the mid-grade res spell (low being 'Raise Dead' at 5th and high being 'True Resurrection' at 9th).

And yes, a Wizard or Sorcerer can cast a 'Wish' spell to duplicate the effects of a chosen spell from any class. I usually don't give my players too much shit for wording on a Wish spell when used to reproduce spell effects.

Also, Psionicists get a similar power at around the same level. The difference is that they are "altering reality through sheer force of will."

"Bring back your dead" magic is really pretty practical in D&D, no matter the edition really. Once the PCs gain enough levels to start using this type of magic they will and that's pretty much a hallmark of the game. Adventurers really have nothing to do with people anymore, they're more on the level with comic book characters. They're superhuman at 3rd - 5th level, they're real powerful from 6th - 9th level, they're sickly powerful from 10th - 13 and they're almost physically inhuman by the time they're going 14 and beyond (if you were to compare them to humans as we know em).

That said, it's all up to you how available you want to make such magic. I tend to make it rare but once the cleric is high enough then they've got access to the spell. You might make it a more demanding ritual, you might make it a spiritual adventure to the underworld to bring back the soul of your comrade but unless you want to remove the spell then it's going to be likely that if the fighter kicks the bucket the cleric will bring him back.