Data commit

Task/Range-extraction/Dyalect/range-extraction.dyalect

@@ -0,0 +1,39 @@
+func rangeFormat(a) {
+    if a.Length() == 0 {
+        return ""
+    }
+    var parts = []
+    var n1 = 0
+    while true {
+        var n2 = n1 + 1
+        while n2 < a.Length() && a[n2] == a[n2-1]+1 {
+            n2 += 1
+        }
+        var s = a[n1].ToString()
+        if n2 == n1+2 {
+            s += "," + a[n2-1]
+        } else if n2 > n1+2 {
+            s += "-" + a[n2-1]
+        }
+        parts.Add(s)
+        if n2 == a.Length() {
+            break
+        }
+        if a[n2] == a[n2-1] {
+            throw "Sequence repeats value \(a[n2])"
+        }
+        if a[n2] < a[n2-1] {
+            throw "Sequence not ordered: \(a[n2]) < \(a[n2-1])"
+        }
+        n1 = n2
+    }
+    return String.Join(values: parts)
+}
+
+var rf = rangeFormat([
+    0, 1, 2, 4, 6, 7, 8, 11, 12, 14,
+    15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
+    25, 27, 28, 29, 30, 31, 32, 33, 35, 36,
+    37, 38, 39
+])
+print("range format: \(rf)")