Youll Shoot Your Eye Out

Common objection when someone inexperienced with a particular tool/methodology/language/whatever, desires to use an advanced/dangerous feature thereof (which ought only be attempted by experienced users, and even then only under certain conditions).

JuniorProgrammer?: Can you tell me, o wizard, how to use reinterpret_cast<> correctly?
GrandMasterProgrammer: Careful, there, YoullShootYourEyeOut!

Comes from ChristmasStoryMovie

Related: HowToShootYourselfInTheFoot in many programming languages.

Sometimes rendered as YoullPutYourEyeOut? in the USA. Companion phrase to YoullBreakYourNeck?

Remember - it's all a game until someone loses an eye - then it's a sport!

CategoryIdiom