Word class / part of speech of 'whoever' [closed]

The compound pronoun "whoever" is found in 'fused' relative constructions and in the exhaustive interrogative construction which functions as an adjunct:

[1] Invite [whoever you want].

[2] I shan't be attending the meeting, [whoever takes over the chair].

In the fused relative construction in [1] "whoever" has a free choice meaning: you can invite anyone you want; it's non-referential -- it's for you to decide who you invite.

In [2], the exhaustive interrogative construction uses an interrogative clause to express a set of conditions that exhaustively cover the possibilities. "I shan't be attending the meeting if 'x' takes over the chair and I shan't be attending if 'y' takes over the chair; I shan't be attending the meeting whoever takes over the chair.