Implement basic, -n and -b functionality for 'cat' command alternative

Author: Geraldine-Edwards

implement-shell-tools/cat/cat.py

@@ -0,0 +1,44 @@
+import argparse
+
+
+parser = argparse.ArgumentParser(
+    prog="cat",
+    description="An alternative to the 'cat' command",
+)
+
+parser.add_argument("files", nargs="+", help="The file(s) to process")
+parser.add_argument("-n", "--number", action="store_true", help="Number all output lines")
+parser.add_argument("-b", "--number-nonblank", action="store_true", help="Number non-blank output lines")
+
+args = parser.parse_args()
+
+
+
+def print_line(line, padding_width, line_number=None):
+    """Helper function to print a line with optional line numbering."""
+    if line_number is not None:
+        print(f"{str(line_number).rjust(padding_width)}  {line}")
+    else:
+        print(line)
+
+line_number = 1 
+padding_width = 6  
+
+for file in args.files:
+    with open(file, "r") as f:
+        # read the content and split the lines ready to process as needed
+        content = f.read().splitlines()
+
+    for line in content:
+        # use .strip() to remove leading and trailing whitespace or /n
+        if args.number_nonblank and line.strip():
+            # number non-blank lines only
+            print_line(line, padding_width, line_number)
+            line_number += 1
+        elif args.number:
+            # number all lines
+            print_line(line, padding_width, line_number)
+            line_number += 1
+        else:
+            # no flags
+            print_line(line, padding_width)