Open Radar

 
Summary:
I believe the compiler is incorrectly giving a "missing argument label error" in the following situation:

public func flip<A, B, C>(f: A -> B -> C)(b: B)(a: A) -> C {
    return f(a)(b)
}

public func useFlip() {
    let subtract = { (x:Int) in { y in x-y }}
    let result = flip(subtract)(5)(3);

    subtract(4)(3);
}

The compiler complains about no b label in front of the 5 and no a label in front of the 3. If I put an underscore in front of the a and b parameters in flip then in addition to the compiler errors I get compiler warnings.

Errors:
/Users/mgwelch/Documents/Projects/thirdparty/swiftz/swiftz_core/swiftz_coreTests/FunctionSpecs.swift:7:33: Missing argument label 'b:' in call
/Users/mgwelch/Documents/Projects/thirdparty/swiftz/swiftz_core/swiftz_coreTests/FunctionSpecs.swift:7:36: Missing argument label 'a:' in call

Steps to Reproduce:
I've attached a complete file.

1. Create a playground
2. Paste the code

Or

1. Create a Swift project
2. Add the attached file
3. Compile



Expected Results:
I expect that I could call the following without labels

flip(subtract)(5)(3)

Actual Results:
I get errors and need to add labels. Normally whenever you have a parameter that requires labels you can "fix" the problem by adding underscores in front of the parameter name in the function definition. But that doesn't fix the problem in this case and instead you end up with 2 compiler warnings in addition to the compiler errors.

Version:
XCode 6.1
OS X 10.10

Notes:


Configuration:


Attachments:
'FunctionSpecs.swift' was successfully uploaded.
public func flip<A, B, C>(f: A -> B -> C)(b: B)(a: A) -> C {
    return f(a)(b)
}

public func useFlip() {
    let subtract = { (x:Int) in { y in x-y }}
    let result = flip(subtract)(5)(3);

    subtract(4)(3);
}