Data commit

Task/Closures-Value-capture/R/closures-value-capture-1.r

@@ -0,0 +1,9 @@
+# assign 's' a list of ten functions
+s <- sapply (1:10,  # integers 1..10 become argument 'x' below
+    function (x) {
+        x  # force evaluation of promise x
+	function (i=x) i*i   # this *function* is the return value
+    })
+
+s[[5]]()  # call the fifth function in the list of returned functions
+[1] 25    # returns vector of length 1 with the value 25

Task/Closures-Value-capture/R/closures-value-capture-2.r

@@ -0,0 +1,2 @@
+s[[5]](10)
+[1] 100

Task/Closures-Value-capture/R/closures-value-capture-3.r

@@ -0,0 +1,18 @@
+s <- sapply (1:10,
+    function (x) {
+        x  # force evaluation of promise x
+	function () {
+            R <- x*x
+            # evaluate the language expression "x <- x + 1" in the persistent parent environment
+            evalq (x <- x + 1, parent.env(environment()))
+            R  # return squared value
+    }})
+
+s[[5]]()
+[1] 25     # 5^2
+s[[5]]()
+[1] 36     # now 6^2
+s[[1]]()
+[1] 1      # 1^2
+s[[1]]()
+[1] 4      # now 2^2

Task/Closures-Value-capture/R/closures-value-capture-4.r

@@ -0,0 +1 @@
+    evalq (x <- x + 1, parent.env(environment()))

Task/Closures-Value-capture/R/closures-value-capture-5.r

@@ -0,0 +1 @@
+    x <<- x + 1