Add `safeAfter` helper function to `Maybe` name space

With all those crazy value | undefined or Something | Another | Something Else returning functions in the wild it may be handy to take care of lifting the result of functions into a Maybe based on a some predicate. While safeLift can be used to check an input before calling a function, the typical compose(safe(pred), someFunc) can be replaced with this safeAfter function. It has the following signature:

safeLift :: ((a -> Boolean) | Pred) -> (a -> b) -> a -> Maybe b

This will need the following to be accomplished:

• Add code:
  • src/Maybe/safeAfter.js
• Add specs
  • src/Maybe/safeAfter.spec.js
• Documentation
  • Update ReadMe (src/Maybe/README.md)
  • Add to Docs with description and example usage (docs/src/pages/docs/crocks/Maybe.md)
  • Add link to Helpers Section (docs/src/pages/docs/functions/index.md)
• Expose new functions to public API (src/index.js)
  • Entry for safeAfter
• Add specs for new public functions (src/index.spec.js)
  • Entry for safeAfter

[karthikiyengar]

@evilsoft - Also, I’m pretty sure it’s a typo, but I just wanted to confirm for good measure - the returned function should be returning Just(result), right? (instead of Just(x)).

[evilsoft]

This has been completed and merged, will go out in the next release 0.9.1