diff --git a/Sources/Common/CodeLength.swift b/Sources/Common/CodeLength.swift
index bea23541..788886ad 100644
--- a/Sources/Common/CodeLength.swift
+++ b/Sources/Common/CodeLength.swift
@@ -10,6 +10,25 @@ struct CodeLength: Equatable {
     let symbol: Int
     let codeLength: Int
 
+    static func lengths(from bootstrap: [(symbol: Int, codeLength: Int)]) -> [CodeLength] {
+        // Fills the 'lengths' array with pairs of (symbol, codeLength) from a 'bootstrap'.
+        var lengths = [CodeLength]()
+        var start = bootstrap[0].symbol
+        var bits = bootstrap[0].codeLength
+        for pair in bootstrap[1..<bootstrap.count] {
+            let finish = pair.symbol
+            let endbits = pair.codeLength
+            if bits > 0 {
+                for i in start..<finish {
+                    lengths.append(CodeLength(symbol: i, codeLength: bits))
+                }
+            }
+            start = finish
+            bits = endbits
+        }
+        return lengths
+    }
+
 }
 
 extension CodeLength: Comparable {
diff --git a/Sources/Deflate/Deflate+Constants.swift b/Sources/Deflate/Deflate+Constants.swift
index eabc3fc5..8051da7b 100644
--- a/Sources/Deflate/Deflate+Constants.swift
+++ b/Sources/Deflate/Deflate+Constants.swift
@@ -9,8 +9,8 @@ extension Deflate {
 
     struct Constants {
         // Bootstraps for Static Huffman trees (first element in tuple is code, second is number of bits).
-        static let staticHuffmanBootstrap = Deflate.lengths(from: [(0, 8), (144, 9), (256, 7), (280, 8), (288, -1)])
-        static let staticHuffmanDistancesBootstrap = Deflate.lengths(from: [(0, 5), (32, -1)])
+        static let staticHuffmanBootstrap = CodeLength.lengths(from: [(0, 8), (144, 9), (256, 7), (280, 8), (288, -1)])
+        static let staticHuffmanDistancesBootstrap = CodeLength.lengths(from: [(0, 5), (32, -1)])
 
         static let codeLengthOrders: [Int] =
             [16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15]
diff --git a/Sources/Deflate/Deflate+Lengths.swift b/Sources/Deflate/Deflate+Lengths.swift
index 6a5a3b8e..7917e511 100644
--- a/Sources/Deflate/Deflate+Lengths.swift
+++ b/Sources/Deflate/Deflate+Lengths.swift
@@ -8,25 +8,6 @@ import Foundation
 // Deflate specific functions for generation of HuffmanLength arrays from different inputs.
 extension Deflate {
 
-    static func lengths(from bootstrap: [(symbol: Int, codeLength: Int)]) -> [CodeLength] {
-        // Fills the 'lengths' array with pairs of (symbol, codeLength) from a 'bootstrap'.
-        var lengths = [CodeLength]()
-        var start = bootstrap[0].symbol
-        var bits = bootstrap[0].codeLength
-        for pair in bootstrap[1..<bootstrap.count] {
-            let finish = pair.symbol
-            let endbits = pair.codeLength
-            if bits > 0 {
-                for i in start..<finish {
-                    lengths.append(CodeLength(symbol: i, codeLength: bits))
-                }
-            }
-            start = finish
-            bits = endbits
-        }
-        return lengths
-    }
-
     /// - Note: Skips zero codeLengths.
     static func lengths(from orderedCodeLengths: [Int]) -> [CodeLength] {
         var lengths = [CodeLength]()