     }
 }
 
-extension SwiftDeclarationKind {
+private extension SwiftDeclarationKind {
     static let varKinds: [SwiftDeclarationKind] = [.varGlobal, .varClass, .varLocal, .varStatic, .varInstance]
 }
 
-extension File {
+private extension File {
     func line(for byteOffset: Int, startFrom: Int) -> Int {
         for index in startFrom..<lines.count {
             let line = lines[index]

import Foundation
import SourceKittenFramework

public struct LetVarWhitespaceRule: OptInRule {

    public var configurationDescription: String { return "" }

    public init() {}
    public init(configuration: Any) {}

    public static let description = RuleDescription(
        identifier: "let_var_whitespace",

    }

    // Collects all the line numbers containing comments or #if/#endif
    private func skippedLineNumbers(file: File) -> Set<Int> {
        var result = Set<Int>()
        let syntaxMap = file.syntaxMap

