From b24d4208e42ee25d3cc3da713b75590eadedf94f Mon Sep 17 00:00:00 2001
From: Adrian Cochrane <adrian@openwork.nz>
Date: Sun, 19 Apr 2020 10:58:16 +1200
Subject: [PATCH] Optimize: use HashMap.Lazy for cascade.

---
 src/Data/CSS/Style/Cascade.hs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/Data/CSS/Style/Cascade.hs b/src/Data/CSS/Style/Cascade.hs
index 698da67..68a0c32 100644
--- a/src/Data/CSS/Style/Cascade.hs
+++ b/src/Data/CSS/Style/Cascade.hs
@@ -12,6 +12,7 @@ import Data.CSS.Syntax.Tokens
 -- TODO do performance tests to decide beside between strict/lazy,
 --      or is another Map implementation better?
 import Data.HashMap.Strict
+import qualified Data.HashMap.Lazy as HML
 import Data.Text (unpack, pack, isPrefixOf)
 
 -- | Defines how to parse CSS properties into an output "style" format.
@@ -63,12 +64,12 @@ query self el = Prelude.foldr yield empty $ lookupRules self el
 -- parsed to a value of the same `PropertyParser` type passed in & inheriting from it.
 cascade :: PropertyParser p => [StyleRule'] -> Props -> p -> p
 cascade styles overrides base =
-    construct base $ toList $ cascadeRules (getVars base ++ overrides) styles
+    construct base $ HML.toList $ cascadeRules (getVars base ++ overrides) styles
 
 cascadeRules :: Props -> [StyleRule'] -> HashMap Text [Token]
 cascadeRules overrides rules = cascadeProperties overrides $ concat $ Prelude.map properties rules
 cascadeProperties :: Props -> Props -> HashMap Text [Token]
-cascadeProperties overrides props = fromList (props ++ overrides)
+cascadeProperties overrides props = HML.fromList (props ++ overrides)
 
 construct :: PropertyParser p => p -> Props -> p
 construct base props = dispatch base child props
-- 
2.30.2