From: Lucas Bajolet <r4pass@hotmail.com>
Date: Tue, 25 Mar 2014 19:42:09 +0000 (-0400)
Subject: stdlib/strings: Added cache for efficency when calling to_cstring on FlatTexts.
X-Git-Tag: v0.6.5~7^2~3^2~4
X-Git-Url: http://nitlanguage.org

stdlib/strings: Added cache for efficency when calling to_cstring on FlatTexts.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
---

diff --git a/lib/standard/string.nit b/lib/standard/string.nit
index 11dece3..ecf7cf1 100644
--- a/lib/standard/string.nit
+++ b/lib/standard/string.nit
@@ -470,6 +470,9 @@ abstract class FlatText
 
 	private var items: NativeString
 
+	# Real items, used as cache for to_cstring is called
+	private var real_items: nullable NativeString = null
+
 	redef var length: Int
 
 	init do end
@@ -733,10 +736,12 @@ class FlatString
 	# Return a null terminated char *
 	redef fun to_cstring: NativeString
 	do
+		if real_items != null then return real_items.as(not null)
 		if index_from > 0 or index_to != items.cstring_length - 1 then
 			var newItems = calloc_string(length + 1)
 			self.items.copy_to(newItems, length, index_from, 0)
 			newItems[length] = '\0'
+			self.real_items = newItems
 			return newItems
 		end
 		return items
@@ -1043,10 +1048,13 @@ class FlatBuffer
 
 	redef fun to_cstring
 	do
-		var new_native = calloc_string(length + 1)
-		new_native[length] = '\0'
-		items.copy_to(new_native, length, 0, 0)
-		return new_native
+		if real_items == null then
+			var new_native = calloc_string(length + 1)
+			new_native[length] = '\0'
+			items.copy_to(new_native, length, 0, 0)
+			real_items = new_native
+		end
+		return real_items.as(not null)
 	end
 
 	# Create a new empty string.