diff options
| -rw-r--r-- | lib/modules.nix | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/lib/modules.nix b/lib/modules.nix index 559697b3d57..228cde002db 100644 --- a/lib/modules.nix +++ b/lib/modules.nix @@ -365,16 +365,9 @@ rec { else mergeDefinitions loc opt.type defs'; - - # The value with a check that it is defined - valueDefined = if res.isDefined then res.mergedValue else - # (nixos-option detects this specific error message and gives it special - # handling. If changed here, please change it there too.) - throw "The option `${showOption loc}' is used but not defined."; - # Apply the 'apply' function to the merged value. This allows options to # yield a value computed from the definitions - value = if opt ? apply then opt.apply valueDefined else valueDefined; + value = if opt ? apply then opt.apply res.mergedValue else res.mergedValue; in opt // { value = builtins.addErrorContext "while evaluating the option `${showOption loc}':" value; @@ -408,11 +401,17 @@ rec { }; defsFinal = defsFinal'.values; - # Type-check the remaining definitions, and merge them. - mergedValue = foldl' (res: def: - if type.check def.value then res - else throw "The option value `${showOption loc}' in `${def.file}' is not of type `${type.description}'.") - (type.merge loc defsFinal) defsFinal; + # Type-check the remaining definitions, and merge them. Or throw if no definitions. + mergedValue = + if isDefined then + foldl' (res: def: + if type.check def.value then res + else throw "The option value `${showOption loc}' in `${def.file}' is not of type `${type.description}'." + ) (type.merge loc defsFinal) defsFinal + else + # (nixos-option detects this specific error message and gives it special + # handling. If changed here, please change it there too.) + throw "The option `${showOption loc}' is used but not defined."; isDefined = defsFinal != []; |