I cancan't replicate your warning. 
>perl -we"my ($dginput, $volinput) = map { chomp; lc } <>;"
a
b
c
^Z

[download]

Not even if I remove the assignment. 

>perl -we"map { chomp; lc } <>;"
a
b
c
^Z

[download]

Tested with 5.6, 5.8 and 5.10

In reply to Re^3: diamond operator multiple input by ikegami
in thread diamond operator multiple input by mikejones

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