I tend to agree that differentiating between "argument not passed" and "argument is undef" is tricky, and from experience with my own modules there is a simple situation where it is problematic: un-setting individual arguments later. You can say function(%defaults, option=>undef) to override $defaults{option} back to undef, but removing a key from %defaults is not really a viable option when, just for example, the defaults and overriding options come from JSON files.

In reply to Re^2: Existing module for PerlX::Maybe except for hash existence? by haukex
in thread Existing module for PerlX::Maybe except for hash existence? by Corion

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