NoSQL operator: islist

Checks that a file has a valid NoSQL 'list' format.

Usage: islist [options]

Options:
    --input (-i) 'file'
      Read input from 'file' instead of STDIN.

    --verbose (-v)
      Set verbose reporting.

    --edit (-E)
      Used by the 'edit*' operators.

    --allow-duplicates (-a)
      Allow duplicated column names.

    --relaxed (-r)
      Allow column names beginning with an underscore '_'.
      Implies '-a'.

    --help (-h)
      Display this help text.

Notes:

The exit code is 0 if the file has a valid NoSQL 'list' structure,
or 255 otherwise. If '--edit' is specified, then a message is
printed to STDOUT telling the number of the first failing row.