DArgBody::not-a-desc
Key: DArgBody::not-a-desc
Category: description · Severity: error
Source: src/diag/hints.nix:846
the body of arg must produce a description (Desc I), not an ordinary value. Build one with descRet, descArg, descRec, descPi, or descPlus.
Example
Hint::DArgBody::not-a-desc means the DArgBody position uses an ordinary term where the checker needs a Desc. The example shows the failing form first, then one way to give the checker the missing structure.
# Bad: the body returns an ordinary term.
descArg nat (_: natLit 0)
# Better: the body returns a description.
descArg nat (_: descRet tt)