X-Git-Url: http://nitlanguage.org

diff --git a/lib/standard/string.nit b/lib/standard/string.nit
index 0b4b1e9..e78f655 100644
--- a/lib/standard/string.nit
+++ b/lib/standard/string.nit
@@ -350,12 +350,12 @@ abstract class Text
 	#
 	#     assert " \n\thello \n\t".l_trim == "hello \n\t"
 	#
-	# A whitespace is defined as any character which ascii value is less than or equal to 32
+	# `Char::is_whitespace` determines what is a whitespace.
 	fun l_trim: SELFTYPE
 	do
 		var iter = self.chars.iterator
 		while iter.is_ok do
-			if iter.item.ascii > 32 then break
+			if not iter.item.is_whitespace then break
 			iter.next
 		end
 		if iter.index == length then return self.empty
@@ -366,12 +366,12 @@ abstract class Text
 	#
 	#     assert " \n\thello \n\t".r_trim == " \n\thello"
 	#
-	# A whitespace is defined as any character which ascii value is less than or equal to 32
+	# `Char::is_whitespace` determines what is a whitespace.
 	fun r_trim: SELFTYPE
 	do
 		var iter = self.chars.reverse_iterator
 		while iter.is_ok do
-			if iter.item.ascii > 32 then break
+			if not iter.item.is_whitespace then break
 			iter.next
 		end
 		if iter.index < 0 then return self.empty
@@ -379,12 +379,29 @@ abstract class Text
 	end
 
 	# Trims trailing and preceding white spaces
-	# A whitespace is defined as any character which ascii value is less than or equal to 32
 	#
 	#     assert "  Hello  World !  ".trim   == "Hello  World !"
 	#     assert "\na\nb\tc\t".trim          == "a\nb\tc"
+	#
+	# `Char::is_whitespace` determines what is a whitespace.
 	fun trim: SELFTYPE do return (self.l_trim).r_trim
 
+	# Is the string non-empty but only made of whitespaces?
+	#
+	#    assert " \n\t ".is_whitespace    == true
+	#    assert "  hello  ".is_whitespace == false
+	#    assert "".is_whitespace          == false
+	#
+	# `Char::is_whitespace` determines what is a whitespace.
+	fun is_whitespace: Bool
+	do
+		if is_empty then return false
+		for c in self.chars do
+			if not c.is_whitespace then return false
+		end
+		return true
+	end
+
 	# Returns `self` removed from its last line terminator (if any).
 	#
 	#    assert "Hello\n".chomp == "Hello"
@@ -1052,7 +1069,7 @@ class FlatString
 	# Indes in _items of the last item of the string
 	private var index_to: Int is noinit
 
-	redef var chars: SequenceRead[Char] = new FlatStringCharView(self)
+	redef var chars: SequenceRead[Char] = new FlatStringCharView(self) is lazy
 
 	redef fun [](index)
 	do
@@ -1526,7 +1543,7 @@ class FlatBuffer
 	super FlatText
 	super Buffer
 
-	redef var chars: Sequence[Char] = new FlatBufferCharView(self)
+	redef var chars: Sequence[Char] = new FlatBufferCharView(self) is lazy
 
 	private var capacity: Int = 0
 
@@ -1614,6 +1631,20 @@ class FlatBuffer
 	# Create a new empty string.
 	init do end
 
+	# Low-level creation a new buffer with given data.
+	#
+	# `items` will be used as is, without copy, to store the characters of the buffer.
+	# Aliasing issues is the responsibility of the caller.
+	#
+	# If `items` is shared, `written` should be set to true after the creation
+	# so that a modification will do a copy-on-write.
+	private init with_infos(items: NativeString, capacity, length: Int)
+	do
+		self.items = items
+		self.length = length
+		self.capacity = capacity
+	end
+
 	# Create a new string copied from `s`.
 	init from(s: Text)
 	do
@@ -1638,7 +1669,6 @@ class FlatBuffer
 	init with_capacity(cap: Int)
 	do
 		assert cap >= 0
-		# _items = new NativeString.calloc(cap)
 		items = new NativeString(cap+1)
 		capacity = cap
 		length = 0
@@ -1682,11 +1712,10 @@ class FlatBuffer
 		if from < 0 then from = 0
 		if count > length then count = length
 		if from < count then
-			var r = new FlatBuffer.with_capacity(count - from)
-			while from < count do
-				r.chars.push(items[from])
-				from += 1
-			end
+			var len = count - from
+			var r_items = new NativeString(len)
+			items.copy_to(r_items, len, from, 0)
+			var r = new FlatBuffer.with_infos(r_items, len, len)
 			return r
 		else
 			return new FlatBuffer