A range function

2 files changed, 4 insertions, 0 deletions

diff --git a/README.md b/README.md
index fa84f62..316f5bf 100644
--- a/README.md
+++ b/README.md
@@ -103,6 +103,7 @@ Other built-in functions are:
 * `take(n list)`: return the first n elements of a list
 * `drop(n list)`: return the list dropping the n first elements
 * `display(value)`: prints its arguments to the screen, for example `display("hello" "world")`
+* `..(i j)`: generate a list of integers from i to j
 
 See the examples in `./examples`.
 
diff --git a/funco b/funco
index 55e22ab..0c27211 100755
--- a/funco
+++ b/funco
@@ -411,6 +411,9 @@ def default_env():
             "take": lambda n, xs: xs[:n],
             "drop": lambda n, xs: xs[n:],
             "display": print,
+            "..": lambda f, t: list(range(f, t + 1, 1) if f < t else range(f, t - 1, -1)) if (
+                isinstance(f, int) and isinstance(t, int)
+                ) else None
         }
     )
     return env