I found this old thread (from over a year ago), which explains how come R doesn't support a multi-line comments (like /* comment */ of PHP, for example).
I am wondering if this has been resolved in the past year, or if there are other alternatives? (For example, in notepad++ with npptor, you can mark a bunch of lines and press ctrl+q to mark them all as comments, are there similar solutions for other IDE's ?)
R Studio (and Eclipse + StatET): Highlight the text and use CTRL+SHIFT+C to comment multiple lines in Windows. Or, command+SHIFT+C in OS-X.