416. A conditional clause may be introduced by whoever, whenever, or some similar compound ([§§ 159], [195]).

Note. In older English and in poetry, who is common in this construction: as,—“Who [= whoever] steals my purse, steals trash” (Shakspere).

417. A conditional clause sometimes omits the copula and its subject.

The if-clause is sometimes used as an exclamation, with the conclusion omitted.

If I only had a rifle!

418. A condition may be expressed by means of an assertion, a question, an imperative, or the absolute construction ([§ 345]).

Note. In such cases, there is no subordinate conditional clause. Thus, in the first example, we have two independent coördinate clauses, making a compound sentence ([§ 44]).