{
  "name": "strpos",
  "type": "function",
  "description": "Return the first matching position of a substring within another string, or 0 if the substring is not found.",
  "arguments": [ {"arg":"haystack","description":"string that is to be searched"},
                 {"arg":"needle","description":"string to search for"}],
  "examples": [ { "expression":"strpos('HELLO WORLD','WORLD')", "returns":"7"},
  { "expression":"strpos('HELLO WORLD','GOODBYE')", "returns":"0"}
  ]
}