From: Lucas Bajolet <r4pass@hotmail.com>
Date: Mon, 24 Mar 2014 15:53:58 +0000 (-0400)
Subject: stdlib/strings: Moved, factorized and generalized comparison operators to Text.
X-Git-Tag: v0.6.5~7^2~3^2~17
X-Git-Url: http://nitlanguage.org

stdlib/strings: Moved, factorized and generalized comparison operators to Text.

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

diff --git a/lib/standard/string.nit b/lib/standard/string.nit
index 1dcbb31..703db45 100644
--- a/lib/standard/string.nit
+++ b/lib/standard/string.nit
@@ -27,6 +27,9 @@ intrude import collection # FIXME should be collection::array
 
 # High-level abstraction for all text representations
 abstract class Text
+	super Comparable
+
+	redef type OTHER: Text
 
 	# Gets a view on the chars of the Text object
 	fun chars: StringCharView is abstract
@@ -421,6 +424,20 @@ abstract class Text
 		return res.to_s
 	end
 
+	redef fun ==(o)
+	do
+		if o == null then return false
+		if not o isa Text then return false
+		if self.is_same_instance(o) then return true
+		if self.length != o.length then return false
+		return self.chars == o.chars
+	end
+
+	redef fun <(o)
+	do
+		return self.chars < o.chars
+	end
+
 end
 
 # All kinds of array-based text representations.
@@ -447,9 +464,12 @@ end
 # views on String and Buffer objects
 abstract class StringCharView
 	super SequenceRead[Char]
+	super Comparable
 
 	type SELFTYPE: Text
 
+	redef type OTHER: StringCharView
+
 	private var target: SELFTYPE
 
 	private init(tgt: SELFTYPE)
@@ -507,6 +527,36 @@ abstract class StringCharView
 		return false
 	end
 
+	redef fun ==(other)
+	do
+		if other == null then return false
+		if not other isa StringCharView then return false
+		var other_chars = other.iterator
+		for i in self do
+			if i != other_chars.item then return false
+			other_chars.next
+		end
+		return true
+	end
+
+	redef fun <(other)
+	do
+		var self_chars = self.iterator
+		var other_chars = other.iterator
+
+		while self_chars.is_ok and other_chars.is_ok do
+			if self_chars.item < other_chars.item then return true
+			if self_chars.item > other_chars.item then return false
+			self_chars.next
+			other_chars.next
+		end
+
+		if self_chars.is_ok then
+			return false
+		else
+			return true
+		end
+	end
 end
 
 # View on Buffer objects, extends Sequence
@@ -521,12 +571,9 @@ end
 
 # Immutable strings of characters.
 class String
-	super Comparable
 	super FlatText
 	super StringCapable
 
-	redef type OTHER: String
-
 	# Index in _items of the start of the string
 	private var index_from: Int
 
@@ -664,7 +711,7 @@ class String
 
 	redef fun ==(other)
 	do
-		if not other isa String then return false
+		if not other isa String then return super
 
 		if self.object_id == other.object_id then return true
 
@@ -694,6 +741,8 @@ class String
 	#     assert ("aa" < "b")      ==  true
 	redef fun <(other)
 	do
+		if not other isa String then return super
+
 		if self.object_id == other.object_id then return false
 
 		var my_curr_char : Char
@@ -897,12 +946,9 @@ end
 # Mutable strings of characters.
 class FlatBuffer
 	super FlatText
-	super Comparable
 	super StringCapable
 	super Buffer
 
-	redef type OTHER: String
-
 	redef var chars: FlatBufferCharView = new FlatBufferCharView(self)
 
 	var capacity: Int
@@ -950,28 +996,6 @@ class FlatBuffer
 		return a.to_s_with_length(length)
 	end
 
-	redef fun <(s)
-	do
-		var i = 0
-		var l1 = length
-		var l2 = s.length
-		while i < l1 and i < l2 do
-			var c1 = self.chars[i].ascii
-			var c2 = s.chars[i].ascii
-			if c1 < c2 then
-				return true
-			else if c2 < c1 then
-				return false
-			end
-			i += 1
-		end
-		if l1 < l2 then
-			return true
-		else
-			return false
-		end
-	end
-
 	# Create a new empty string.
 	init
 	do
@@ -1004,21 +1028,6 @@ class FlatBuffer
 		length += sl
 	end
 
-	redef fun ==(o)
-	do
-		if not o isa FlatBuffer then return false
-		var l = length
-		if o.length != l then return false
-		var i = 0
-		var it = items
-		var oit = o.items
-		while i < l do
-			if it[i] != oit[i] then return false
-			i += 1
-		end
-		return true
-	end
-
 	# Copies the content of self in `dest`
 	fun copy(start: Int, len: Int, dest: Buffer, new_start: Int)
 	do