LONDON | DONARA BLANC | SHELL TOOLS - PYTHON | SPRINT 4

implement-shell-tools/cat/cat.py

@@ -0,0 +1,41 @@
+import sys
+
+def cat(files, number_all=False, number_nonblank=False):
+    line_number = 1
+    for file in files:
+        try:
+            with open(file, 'r') as f:
+                for line in f:
+                    if number_nonblank:
+                        if line.strip() != "":
+                            print(f"{line_number}\t{line}", end='')
+                            line_number += 1
+                        else:
+                            print(line, end='')
+                    elif number_all:
+                        print(f"{line_number}\t{line}", end='')
+                        line_number += 1
+                    else:
+                        print(line, end='')
+        except FileNotFoundError:
+            print(f"cat: {file}: No such file or directory", file=sys.stderr)
+
+if __name__ == "__main__":
+    args = sys.argv[1:]
+    number_all = False
+    number_nonblank = False
+    files = []
+
+    for arg in args:
+        if arg == '-n':
+            number_all = True
+        elif arg == '-b':
+            number_nonblank = True
+        else:
+            files.append(arg)
+
+    # -b overrides -n
+    if number_nonblank:
+        number_all = False
+
+    cat(files, number_all, number_nonblank)

implement-shell-tools/ls/ls.py

@@ -0,0 +1,27 @@
+import os
+import sys
+
+show_all ="-a" in sys.argv
+
+paths = [arg for arg in sys.argv[1:] if not arg.startswith("-")]
+
+if not paths:
+    paths =["."]
+
+for path in paths:
+    if os.path.isdir(path):
+        try:
+            entries = sorted(os.listdir(path))
+            for entry in entries:
+                if show_all or not entry.startswith("."):
+                    print(entry)
+        except Exception as e:
+            print(f"ls: cannot access '{path}': {e}")
+    elif os.path.isfile(path):
+        print(os.path.basename(path))
+    else:
+        print (f"ls:'{path}': no such file or directory")
+
+
+
+

implement-shell-tools/wc/wc.py

@@ -0,0 +1,19 @@
+import sys
+def count_file(filename):
+    try:
+        with open (filename, 'r', encoding='utf-8') as f:
+            content =f.read()
+
+            lines = content.splitlines()
+            words = content.split()
+            characters = content
+
+            print(f"{len(lines)} {len(words)} {len(characters)} {filename}")
+    except FileNotFoundError:
+        print(f"wc:{filename}: no such file or directory")
+
+
+if __name__ == "__main__":
+    args = sys.argv[1:]
+    for file in args:
+        count_file(file)