idlwave-completion-force-default-case

idlwave-completion-force-default-case is a variable defined in `idlwave.el'.
Its value is

nil

Documentation:
Non-nil means, completion will always honor `idlwave-completion-case'.
When nil, only the completion of a mixed case or upper case string
will honor the default settings in `idlwave-completion-case', while
the completion of lower case strings will be completed entirely in
lower case.

You can customize this variable.