rspec/rules/S3086/swift/rule.adoc

Making an operator a convenience wrapper around an existing function or method provides additional flexibility to users in how the functionality is called and in what options are passed in.


This rule raises an issue when the function that defines the operation of a operator consists of something other than a single function call.

== Noncompliant Code Example

----
infix operator >< { associativity right precedence 90 }
func >< (left: Double, right: Double) -> Double {  // Noncompliant
  let leftD = (left % 1) * 100
  let rightD = (right % 1) * 100
  let leftW = (left - leftD) / 100
  let rightW = (right - rightD) / 100
  return (leftD + leftW) * (rightD + rightW)
}
----

== Compliant Solution

----
infix operator >< { associativity right precedence 90 }
func >< (left: Double, right: Double) -> Double { 
  return fubar(left, right)
}

func fubar(left: Double, right: Double) -> Double {
  let leftD = (left % 1) * 100
  let rightD = (right % 1) * 100
  let leftW = (left - leftD) / 100
  let rightW = (right - rightD) / 100
  return (leftD + leftW) * (rightD + rightW)
}
----

== Exceptions

Operators that end with ``++=++`` are expected to update their left-hand operands, and are therefore ignored.

----
func **= (inout p1:Int, p2:Int) { 
    p1 = p1 ** p2
}
----