Merge: nitunit the manual

[nit.git] / doc / manual / constructor.md

diff --git a/doc/manual/constructor.md b/doc/manual/constructor.md
index 39bfe53..38a32c3 100644 (file)
--- a/doc/manual/constructor.md
+++ b/doc/manual/constructor.md
@@ -27,6 +27,11 @@ assert p.id == "ABC"
 In subclasses, additional attributes are automatically collected.
 
 ~~~
+class Product
+       var id: String
+       var description: String
+       var price: Float
+end
 class Book
        super Product
        var author: String
@@ -44,6 +49,11 @@ It is used to perform additional systematic tasks.
 Because the `init` is run at the end of the initialization sequence, initialized attributes are usable in the body.
 
 ~~~
+class Product
+       var id: String
+       var description: String
+       var price: Float
+end
 class OverpricedProduct
        super Product
        init
@@ -52,7 +62,7 @@ class OverpricedProduct
        end
 end
 var op = new OverpricedProduct("ABC", "Bla bla", 15.95)
-assert op.price == 159.50
+assert op.price.is_approx(159.50, 0.001)
 ~~~
 
 
@@ -65,6 +75,11 @@ There is three cases for an attributes to not be collected in the `new`.
 * Attributes introduced in refinement of classes
 
 ~~~
+class Product
+       var id: String
+       var description: String
+       var price: Float
+end
 class TaxedProduct
        super Product
        var tax_rate = 9.90
@@ -75,7 +90,7 @@ class TaxedProduct
        end
 end
 var tp = new TaxedProduct("ABC", "Bla bla", 15.95)
-assert tp.total_price == 17.52905
+assert tp.total_price.is_approx(17.52905, 0.00001)
 ~~~
 
 Note: The orchestration here is important. In order, the following is executed:
@@ -95,6 +110,11 @@ In fact, by default, the setter of an attribute is used as a initializer.
 `autoinit` is used to register a method as a setter.
 
 ~~~
+class Product
+       var id: String
+       var description: String
+       var price: Float
+end
 class FooProduct
        super Product
        fun set_xy(x, y: Int) is autoinit do z = x * 10 + y
@@ -113,6 +133,32 @@ In most case, there is no reason that an argument of a `new` construction is not
 As explained above, one of the main advantage of these constructors is their compatibility with multiple inheritance.
 
 ~~~
+class Product
+       var id: String
+       var description: String
+       var price: Float
+end
+class OverpricedProduct
+       super Product
+       init
+       do
+               price = price * 10.0
+       end
+end
+class TaxedProduct
+       super Product
+       var tax_rate = 9.90
+       var total_price: Float is noinit
+       init
+       do
+               total_price = price * (1.0 + tax_rate/100.0)
+       end
+end
+class FooProduct
+       super Product
+       fun set_xy(x, y: Int) is autoinit do z = x * 10 + y
+       var z: Int is noinit
+end
 class MultiProduct
        super OverpricedProduct
        super TaxedProduct
@@ -120,8 +166,8 @@ class MultiProduct
 end
 var mp = new MultiProduct("ABC", "Bla bla", 15.96, 1, 3)
 assert mp.id == "ABC"
-assert mp.price == 159.6
-assert mp.total_price == 175.4
+assert mp.price.is_approx(159.6, 0.001)
+assert mp.total_price.is_approx(175.4, 0.001)
 assert mp.z == 13
 ~~~
 
@@ -151,11 +197,11 @@ class Point
        redef fun to_s do return "({x},{y})"
 end
 var p1 = new Point(1.0, 2.0)
-assert p1.to_s ==  "(1,2)"
+assert p1.to_s ==  "(1.0,2.0)"
 var p2 = new Point.origin
-assert p2.to_s ==  "(0,0)"
+assert p2.to_s ==  "(0.0,0.0)"
 var p3 = new Point.polar(1.0, 2.0)
-assert p3.to_s ==  "(-0.4161,0.9092)"
+assert p3.to_s ==  "(-0.416,0.909)"
 ~~~