shift requires an array (@NAME, @BLOCK, EXPR->@* and similar).

You want a list slice (( LIST )[ INDEXES ]).

Specifically, 

( split( /,/, $_, 2 ) )[ 0 ]

[download]

If you are assigning the result to a scalar, you can also use 

my ( $first ) = split( /,/, $_, 2 );

[download]

Using 2 for split's third operand isn't required; it's an optimization. There's no reason to continue splitting after the first split.

In reply to Re: why can't I shift a split? by ikegami
in thread why can't I shift a split? by Anonymous Monk

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