-o Add template for dd, mm, yy (day-month-year)

[non7top]

As of now there is %(autonumber)s, which allows to add autoincreament number which is handy to get autosort of files. But when there is a new video added to list the numbers will shift and '--no-overwrites' option will become useless, as well as there will now be two files with each number 0001, 0002 etc.

Having day,month,year in template will still make use of no overwrites and will still allow to get latest file in top of list, i.e.
%(yy)s.%(mm)s.%(dd)s-%(title)s.%(ext)s

[phihag]

Day, month, and year would refer to the date of the video (since you can easily use $(date) to get the current date in the filename). Shouldn't be too hard, but we'll have to decide what to print when the number is not available. None? noday? `` (empty string)?

[non7top]

Yes, I meant the video date. As for the case when video date is not available, returning current date seems to be quite reasonable, it will be more close to autoincreament and will not break sorting

[non7top]

After some digging in the code I've found that it is possible to use upload_date in template%(upload_date)s-%(stitle)s.%(ext)s which gives me '20111117-Американский_пирог_Все_в_сборе_Русский_трейлер.mp4' almost exactly what I need.
It might still make sense to have something like --list-template-values and/or --dump to dump the contents of info_dict in order to improve user experience and documentation.

[phihag]

Since some of the info_dict values are an implementation detail, offering to list them would be a bad idea.