Like math_expr() but for a whole vector at once, returning an
expression() (so a discrete ggplot2 scale's labels = can render each
entry as plotmath, mirroring ggplot2::label_parsed() for facet strips).
Like math_expr() but for a whole vector at once, returning an
expression() (so a discrete ggplot2 scale's labels = can render each
entry as plotmath, mirroring ggplot2::label_parsed() for facet strips).