Polass-iMac:~ polashabib$ brew install rbenv ruby-build
==> Searching for similarly named formulae...
Error: No similarly named formulae found.
Error: No available formula or cask with the name "rbenv".
==> Searching for a previously deleted formula (in the last month)...
Error: No previously deleted formula found.
==> Searching taps on GitHub...
Error: No formulae found in taps.
Polass-iMac:~ polashabib$ brew install rbenv
==> Searching for similarly named formulae...
Error: No similarly named formulae found.
Error: No available formula or cask with the name "rbenv".
==> Searching for a previously deleted formula (in the last month)...
Error: No previously deleted formula found.
==> Searching taps on GitHub...
Error: No formulae found in taps.