Much as I like Hall and MacGregor, I wouldn't take their notes as absolute gospel.

Here's what John Greig said about the song, in his 'Scots Minstrelsie'.

'The words of this song were published anonymously in 1803 by Sir Alexander Boswell, Bart, for reference to whom see under 'O Auld Guidman ye're a Drucken Carle'. Of the air Mr. Stenhouse says, 'This beautiful tune has, time out of mind, been played at the breaking up of convivial parties in Scotland'. Granted that this may have been so in the past, 'Auld Langsyne' is the song which in the present time [1890s], almost universally does duty in this respect at Scottish gatherings. In many of the old and important collections of our native minstrelsy, such as Macgibbon's, Oswalds, Johnson's, and R.A. Smith [of Braes of Balquidder fame,] this melody occupies the concluding place.

In Sir Walter Scott's 'Minstrelsy of the Scottish Border' there is a fragment entitled 'Armstrong's Goodnight', which, with Sir Walter's note regarding it may well be quoted here: 'The following verses are said to have been composed by one of the Armstrongs, executed for the murder of Sir John Carmichael of Eldrom, Warden of the Middle Marches. The tune is popular in Scotland, but whether these are the original words will admit of some doubt:

This night is my departing night,
For here nae langer must I stay,
There's neither friend or foe o' mine
But wishes me away.

What I have done thro' lack o' wit,
I never, never can recall,
I hope ye're a' my frieds as yet,
Good-night, and joy be wi' ye all!

'Sir John Carmichael, the Warden, was murdered, 16th June, 1600, by a party of Borderers, at a place called Raesknows, near Lochmaben {Dumfrieshire], whither he was going to hold a Court of Justice. Two of the ringleaders in the slaughter, named 'Ringan's Tam', and Adam Scott, called 'The Pecket', were tried at Edinburgh, at the instance of Carmichael of Edrom. They were comdemned to have their right hands struck off, thereafter to be hanged, and their bodies gibbeted on the Borough Moor, which sentence was executed, 14th November, 1601'.

Other versions of the present song, all based more or less on 'Armstrong's Goodnight', have been written by Joanna Baillie, Lady Nairne, the Ettrick Shepherd [James Hogg], and John Imlah [a progenitor of Hamish Imlach, probably]. To the same air was set Burns's 'Farewell to the Brethern of St. James's Lodge, Tarbolton [Ayrshire]', which, it is said, was sung to the Lodge by the poet when his chest was on the way to Greenock, en route for the West Indies [to which he never went as his book of poems in 1786 earned him a small fortune]. The following quotation fron Burns will conclude our reference to the song:

'Ballad-making is now as completely my hobby as ever fortification was Uncle Toby's, so I'll e'en canter it away till I come to the limit of my race (God grant that I may take the right side of the winning post); and then, cheerfully looking back on the honest folks with whom I have been happy, I shall say or sing, 'Sae merry as we a' ha'e been;' and raising my last looks to the whole human race, the last words of the voice of Coila shall be 'Goodnight and joy be wi' ye a'!'