$var1 ?= die "ERROR: \$var1 already set." : $var2;

[download]

would be far clearer as 

die "ERROR: \$var1 already set." if $var1;

$var1 = $var2;

[download]

In reply to Re^3: RFC: "assignary" operator ?= : by ikegami
in thread RFC: "assignary" operator ?= : by richard.sharpe

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