opt.isDirectory: Error: template commandr.validators.validateEachWith cannot deduce function from argument types !()(Option, void), candidates are:

[mw66]

I tried the example code:

.validateEachWith(opt => opt.isDirectory), "must be a valid directory");

but it errors out:

Error: template commandr.validators.validateEachWith cannot deduce function from argument types !()(Option, void), candidates are:
.dub/packages/commandr-0.1.1/commandr/source/commandr/validators.d(458,10):        validateEachWith(T : IEntry)(T entry, void delegate(IEntry, string) validator)
.dub/packages/commandr-0.1.1/commandr/source/commandr/validators.d(488,10):        validateEachWith(T : IEntry)(T entry, bool delegate(string) validator, string errorMessage)

I changed to isDir or isFile:

https://dlang.org/library/std/file/is_dir.html
https://dlang.org/library/std/file/is_file.html

still doesn't work. Should the function be added in addition to delegate?

And can you add an example.d?

[mw66]

Actually, this is because in the doc, the bracket is in the wrong place:

.validateEachWith(opt => opt.isDirectory), "must be a valid directory")

should be ==>

.validateEachWith(opt => opt.isDir, "must be a valid directory"))