📝Postel’s Law

Be liberal in what you accept, and conservative in what you send. —Jon Postel

Thoughts

• This seems to work better if there multiple co-existing implementations (internet protocols when Postel’s law was formulated). However, if there is one dominant implementation, other code may rely on its particular unspecified behavior which hinders backward compatibility (Being liberal in accepted input hinders backward compatibility).

Counterargument

• Being strict in accepted input allows finding errors

• Being liberal in accepted input hinders backward compatibility