September Morn Update

Task/Add-a-variable-to-a-class-instance-at-runtime/00DESCRIPTION

@@ -1,4 +1,3 @@
-{{omit from|Rust}}
 Demonstrate how to dynamically add variables to an object (a class instance) at runtime.
 
 This is useful when the methods/variables of an instance are based on a data file that isn't available until runtime.  Hal Fulton gives an example of creating an OO CSV parser at [http://www.devsource.com/article2/0,1759,1928562,00.asp An Exercise in Metaprogramming with Ruby].  This is referred to as "monkeypatching" by Pythonistas and some others.

Task/Add-a-variable-to-a-class-instance-at-runtime/Elena/add-a-variable-to-a-class-instance-at-runtime.elena

@@ -1,25 +1,25 @@
-import extensions.
+import extensions;
 
-class Extender :: BaseExtender
+class Extender : BaseExtender
 {
-    object prop foo :: theField.
+    prop object foo;
 
-    constructor new : anObject
-    [
-        theObject := anObject.
-    ]
+    constructor(object)
+    {
+        theObject := object
+    }
 }
 
-public program
-[
-    var anObject := 234.
+public program()
+{
+    var object := 234;
 
     // extending an object with a field
-    anObject := Extender new(anObject).
+    object := new Extender(object);
 
-    anObject foo := "bar".
+    object.foo := "bar";
 
-    console printLine(anObject,".foo=",anObject foo).
+    console.printLine(object,".foo=",object.foo);
 
-    console readChar
-]
+    console.readChar()
+}

Task/Add-a-variable-to-a-class-instance-at-runtime/Go/add-a-variable-to-a-class-instance-at-runtime.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+    "bufio"
+    "fmt"
+    "log"
+    "os"
+)
+
+type SomeStruct struct {
+    runtimeFields map[string]string
+}
+
+func check(err error) {
+    if err != nil {
+        log.Fatal(err)
+    }
+}
+
+func main() {
+    ss := SomeStruct{make(map[string]string)}
+    scanner := bufio.NewScanner(os.Stdin)
+    fmt.Println("Create two fields at runtime: ")
+    for i := 1; i <= 2; i++ {
+        fmt.Printf("  Field #%d:\n", i)
+        fmt.Print("       Enter name  : ")
+        scanner.Scan()
+        name := scanner.Text()
+        fmt.Print("       Enter value : ")
+        scanner.Scan()
+        value := scanner.Text()
+        check(scanner.Err())
+        ss.runtimeFields[name] = value
+        fmt.Println()
+    }
+    for {
+        fmt.Print("Which field do you want to inspect ? ")
+        scanner.Scan()
+        name := scanner.Text()
+        check(scanner.Err())
+        value, ok := ss.runtimeFields[name]
+        if !ok {
+            fmt.Println("There is no field of that name, try again")
+        } else {
+            fmt.Printf("Its value is '%s'\n", value)
+            return
+        }
+    }
+}