textspec
ValuesAdd or remove special, textspec
-related prefixes from text strings.
This is an internal utility function, not intended to be called by package
users.
prefix_text(x, spec, action)
Character vector like x
, with prefixes added or removed. NA values
in x
remain NA.
Character vector to which special prefixes are to be added or removed.
Character vector of valid textspec
values. Recycled to match the
length of x
if action
is "add". Ignored if action
is
"remove".
Character scalar, either "add" or "remove", depending on whether the
special prefix is to be added or removed from x
.
Currently supported textspec
values and the associated prefixes
are: "plain" (no prefix); "plotmath" (prefix MATH_
); and "markdown"
(prefix MKDN_
).
spec_from_text
to derive spec
by looking for special
prefixes in text strings.