## MLton 20241230

# ShowBasisDirective

A comment of the form

    (*#showBasis "<file>"*)

is recognized as a directive to save the current basis (i.e., environment) to `<file>` (in the same format as the `-show-basis <file>` compile-time option). The `<file>` is interpreted relative to the source file in which it appears. The comment is lexed as a distinct token and is parsed as a structure-level declaration. [Note that treating the directive as a top-level declaration would prohibit using it inside a functor body, which would make the feature significantly less useful in the context of the MLton compiler sources (with its nearly fully functorial style).]

This feature is meant to facilitate auto-completion via `company-mlton` and similar tools.