Shorthand Argument

Shorthand arguments like $0, $1, etc. in closures can be confusing. Avoid using them too far away from the beginning of the closure. Optionally, while usage of a single shorthand argument is okay, more than one or complex ones with field accesses might increase the risk of obfuscation.

• Identifier: shorthand_argument
• Enabled by default: No
• Supports autocorrection: No
• Kind: style
• Analyzer rule: No
• Minimum Swift compiler version: 5.0.0
• Default configuration:

  Key	Value
  severity	warning
  allow_until_line_after_opening_brace	4
  always_disallow_more_than_one	false
  always_disallow_member_access	false

Non Triggering Examples

    f { $0 }

    f {
        $0
      + $1
      + $2
    }

    f { $0.a + $0.b }

    f {
        $0
      +  g { $0 }

Triggering Examples

    f {
        $0
      + $1
      + $2

      + ↓$0
    }

    f {
        $0
      + $1
      + $2
      +  5
      + $0
      + ↓$1
    }

    f { ↓$0 + ↓$1 }

    f {
        ↓$0.a
      + ↓$0.b
      + $1
      + ↓$2.c
}