U+21A4 "↤" Leftwards Arrow from Bar Unicode Character

U+21A4 "↤" Leftwards Arrow from Bar is a typographic symbol in the Arrows block, depicting an arrow pointing to the left with a vertical bar at its origin instead of a standard arrow tail. It is often used in mathematics, logic, and computer science to denote a mapping, assignment, or function declaration, particularly in contexts like the "maps to" notation where it represents a relation from a domain to a codomain, such as in the expression x ↤ f(x). Its design conveys a clear directional association while the bar emphasizes a point of departure or initial state.