my %checkers =
   map {; no strict 'refs'; $_ => \&$_ }
      qw( check_char check_time check_date check_numeric );
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or

my %checkers =
   map { $_ => \&$_ }   # \&$_ is except from strict refs.
      qw( check_char check_time check_date check_numeric );
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Then in the loop,

my $checker_name = $rec_layout_hash{$fields[0]}{$i}{"sub_routine"};

my $checker = $checkers{$checker_name}
   or die("Unrecognized checker $checker_name\n");

$checker->($value1, $value2);
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