September 2017 Update

Task/Pascals-triangle/Jq/pascals-triangle-1.jq

@@ -0,0 +1,11 @@
+# pascal(n) for n>=0; pascal(0) emits an empty stream.
+def pascal(n):
+  def _pascal:  # input: the previous row
+    . as $in
+    | .,
+      if length >= n then empty
+      else
+        reduce range(0;length-1) as $i
+          ([1]; . + [ $in[$i] + $in[$i + 1] ]) + [1] | _pascal
+      end;
+  if n <= 0 then empty else [1] | _pascal end ;

Task/Pascals-triangle/Jq/pascals-triangle-2.jq

@@ -0,0 +1,6 @@
+$ jq -c -n -f pascal_triangle.jq
+[1]
+[1,1]
+[1,2,1]
+[1,3,3,1]
+[1,4,6,4,1]

Task/Pascals-triangle/Jq/pascals-triangle-3.jq

@@ -0,0 +1,9 @@
+def pascal(n):
+  if n <= 0 then empty
+  else [1]
+  | recurse( if length >= n then empty
+             else . as $in
+             | reduce range(0;length-1) as $i
+                 ([1]; . + [ $in[$i] + $in[$i + 1] ]) + [1]
+             end)
+  end;