September 2017 Update

Task/Factorial/Jq/factorial-1.jq

@@ -0,0 +1,2 @@
+def fact:
+  reduce range(1; .+1) as $i (1; . * $i);

Task/Factorial/Jq/factorial-2.jq

@@ -0,0 +1,4 @@
+def fact(n):
+  if n <= 1 then n
+  else n * fact(n-1)
+  end;

Task/Factorial/Jq/factorial-3.jq

@@ -0,0 +1,8 @@
+def fact:
+  def _fact:
+    # Input: [accumulator, counter]
+    if .[1] <= 1 then .
+    else [.[0] * .[1], .[1] - 1]|  _fact
+    end;
+  # Extract the accumulated value from the output of _fact:
+  [1, .] | _fact | .[0] ;