What is the syntactic role of “ʿalaykum” in “wa-inna ʿalaykum la-ḥāfiẓīn”?

Supplementary Practice 29 — Comparative Rhetoric of Sūrat al-Infiṭār and Sūrat al-Inshiqāq

• Delayed name of inna
• Cognate accusative
• Fronted predicate of inna
• Single-word circumstantial accusative