Support sampling

1 files changed, 10 insertions, 2 deletions

diff --git a/rl b/rl
index 316e23c..e5a6a92 100755
--- a/rl
+++ b/rl
@@ -28,13 +28,21 @@
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-
+import argparse
 import random
 import sys
 
+parser = argparse.ArgumentParser(description='Process some integers.')
+parser.add_argument('-s', '--sample', metavar='LINES', type=int, nargs='?', const=1, help='Print only this many lines (1).')
+args = parser.parse_args()
+
 lines = sys.stdin.readlines()
 
-random.SystemRandom().shuffle(lines)
+r =  random.SystemRandom()
+if args.sample is None:
+  r.shuffle(lines)
+else:
+  lines = r.sample(lines, args.sample)
 
 for l in lines:
   print(l, end='')