Is there any way to have the same file be a part of multiples changelists in perforce? With that I mean that from the set of changed lines in the file one subset will belong
Another way to do this without branching is create additional workspaces (clients). Unless you really know what you're doing, be sure to set a different root directory in each of your workspaces. To save time (and disk), don't bother syncing the whole depot in the new workspace.
Sometimes, I'll have two copies of a depot (using two workspaces); one which contains work-in-progress and one which I keep unmodified. If I need to make a quickie change on a file that's heavily modified in my WIP workspace, I can use the 'virgin' workspace to make the change and submit it.