Null Reference

An operation or method call was executed on a 'null' or 'nil' value.

Why this error occurs

Accessing properties, calling methods, or indexing a variable whose value is null.

Incorrect Code

let record = null
print(record["id"]) // runtime error: null reference

Corrected Code

let record = null
if record != null:
    print(record["id"])
else:
    print("Record is null")

1Add explicit null checks ('if value != null:') before accessing members.
2Ensure functions returning optional data return a valid object or handle fallback cases.

$ nextviper run <file.nv>$ nextviper check