Tagged lists with multiple tags in mdoc

[Dag-Erling Smørgrav]

I need to make a tagged list where some items have multiple tags - for
instance,

    function1()
    function2()
    function3()
            These are the first three functions.

    function4()
            This is the fourth function.

If I use

.Bl -tag
.It Fn function1
.It Fn function2
.It Fn function3
These are the first three functions.
.It Fn function4
This is the fourth function.
.El

groff will insert blank lines after function1() and function2(), which
I'd like to avoid.  Conversely, if I use -compact, it will omit the
blank lines between before function4() and between the list and the
surrounding text, which is also wrong.

I also tried

.It Fn function1 , Fn function2 , Fn function3

but this is far less readable, and if there are enough items to cause
groff to wrap, the second line will be indented:

    function1(), function2(), function3(), function4(), function5(),
            function6(), function7(), function8()
            These are the first eight functions.

Is there a non-hackish (or not-too-hackish) way to achieve the desired
result?

DES
-- 
Dag-Erling Smørgrav - des at des.no