I disagree with your strategy of preventing a function that returns a scalar from being called in list context. It limits options without adding benefits. (The other way around makes some sense.) But deciding what to have a sub return is a lengthy topic entirely unrelated to the behaviour of the assignment operators. Discussions specifically touching on the appropriateness of using wantarray have surfaced before, once not too long ago. Your thoughts would be better suited in that conversation or in a new conversation.

Also note that our Tutorials section has a tutorial on context.

By the way, syswrite(@_) doesn't work. Due to syswrite's prototype, the call is equivalent to syswrite(scalar(@_)) and results in a compilation error. You need something like: 

if    (@_ == 2) { syswrite($_[0], $_[1]              ) }
elsif (@_ == 3) { syswrite($_[0], $_[1], $_[2]       ) }
elsif (@_ == 4) { syswrite($_[0], $_[1], $_[2], $_[3]) }
else            { die }

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In reply to Re^2: Mini-Tutorial: Scalar vs List Assignment Operator by ikegami
in thread Mini-Tutorial: Scalar vs List Assignment Operator by ikegami

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