pub fn substitute_attributes<'text, 'value>(
text: &'text str,
lookup: impl FnMut(&str) -> Option<&'value DocumentAttributeValue<'value>>,
) -> Cow<'text, str>Expand description
Expand known attribute references once, leaving unresolved references unchanged.
Names contain one or more ASCII letters, digits, underscores, or hyphens.
A backslash before a valid reference is removed and protects that reference
from lookup. Only valid, unescaped references call lookup; inserted values
are not scanned again. Other text and line endings are preserved.
The result borrows the input when no reference is replaced or escape removed.