June 2018 Update

Task/Runtime-evaluation-In-an-environment/Elena/runtime-evaluation-in-an-environment.elena

@@ -0,0 +1,9 @@
+import extensions.
+import extensions'scripting.
+
+program =
+[
+    var program := escript eval("^{ eval(x)[ ^" + 'program'arguments[1] + " ] }").
+
+    console printLine('program'arguments[1],",",'program'arguments[2]," = ", program eval('program'arguments[2] toReal)).
+].

Task/Runtime-evaluation-In-an-environment/Julia/runtime-evaluation-in-an-environment-1.julia

@@ -0,0 +1,10 @@
+macro evalwithx(expr, a, b)
+    return quote
+        x = $a
+        tmp = $expr
+        x = $b
+        return $expr - tmp
+    end
+end
+
+@evalwithx(2 ^ x, 3, 5)     # raw expression (AST)

Task/Runtime-evaluation-In-an-environment/Julia/runtime-evaluation-in-an-environment-2.julia

@@ -0,0 +1,9 @@
+function evalwithx(expr::Expr, a, b)
+    a = eval(quote let x = $a; return $expr end end)
+    b = eval(quote let x = $b; return $expr end end)
+    return b - a
+end
+evalwithx(expr::AbstractString, a, b) = evalwithx(parse(expr), a, b)
+
+evalwithx(:(2 ^ x), 3, 5)
+evalwithx("2 ^ x", 3, 5)

Task/Runtime-evaluation-In-an-environment/Scala/runtime-evaluation-in-an-environment.scala

@@ -0,0 +1,8 @@
+object Eval extends App {
+
+  def evalWithX(expr: String, a: Double, b: Double)=
+    {val x = b; eval(expr)} - {val x = a; eval(expr)}
+
+  println(evalWithX("Math.exp(x)", 0.0, 1.0))
+
+}