Definition 5.3.1 (Net).label Let $X$ be a set and $A$ be an upward-directed set, then a net in $X$ is a mapping $A \to X$, denoted $\net{x}\subset X$.
Definition 5.3.1 (Net).label Let $X$ be a set and $A$ be an upward-directed set, then a net in $X$ is a mapping $A \to X$, denoted $\net{x}\subset X$.