github.com/benhoyt/goawk@v1.8.1/testdata/T.delete (about)

     1  echo T.delete: misc tests of array deletion
     2  
     3  awk=${awk-../a.out}
     4  
     5  echo '1 2 3 4
     6  1 2 3
     7  1
     8  ' >foo0
     9  echo '4 3 0
    10  3 2 0
    11  1 0 0
    12  0 0 0' >foo2
    13  $awk '
    14  {	n = split($0, x)
    15  	delete x[1]
    16  	n1 = 0;	for (i in x) n1++
    17  	delete x; 
    18  	n2 = 0; for (i in x) n2++
    19  	print n, n1, n2
    20  }' foo0 >foo1
    21  diff foo1 foo2 || echo 'BAD: T.delete (1)'