In Waller's poem, "Of English Verse", the final stanza reads:
If it arrive but at the date
Of fading beauty; if it prove
But as long-lived as present love.
The precision in the articulations of "d" and "t" in "the date" contrast with the smooth continuity between "of" and "fading" (which are pushed together by the shared f, not separated), which word group is softened by the leading vowel, taking the edge off the repetition of trochees, thus making "beauty" a pulse rather than a drumbeat, one whose dipthong attempts to stretch it out, but whose final vowel itself, like beauty or poetry, must fade.
The semicolon is our space to mourn. But Waller's metre is more sophisticated than that. Though he depicts it with feeling, Waller does not wish to dwell on the time of beauty or on its fading, but rather on the quality of present love. The movement of the final line-- the tension between the tendencies of the iambic pattern and the habits of normal pronunciation-- reverses the normal relative emphasis of "long-lived" from "long" to "lived", depicting in the metre the argument of the poem: that to write in and for a "lived" present is the best which English poets can do, and that this best is not a gruding limitation, but is in fact rather lovely.