python 24 lines · 6 steps

Printing a directory tree with recursion

A recursive walk renders a filesystem tree with the box-drawing connectors you see in the `tree` command.

Explained by highlit

Intermediate recursion filesystem sorting pathlib tree-traversal

1from pathlib import Path
2 
3 
4def print_tree(root, prefix="", show_hidden=False):
5    root = Path(root)
6    entries = sorted(
7        (p for p in root.iterdir() if show_hidden or not p.name.startswith(".")),
8        key=lambda p: (p.is_file(), p.name.lower()),
9    )
10 
11    for index, entry in enumerate(entries):
12        is_last = index == len(entries) - 1
13        connector = "└── " if is_last else "├── "
14        print(f"{prefix}{connector}{entry.name}{'/' if entry.is_dir() else ''}")
15 
16        if entry.is_dir():
17            extension = "    " if is_last else "│   "
18            print_tree(entry, prefix + extension, show_hidden)
19 
20 
21def render_tree(root, show_hidden=False):
22    root = Path(root)
23    print(f"{root.name or root}/")
24    print_tree(root, show_hidden=show_hidden)

01 / 01

STEP 01

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Three takeaways

1Recursion mirrors a tree's shape: each directory re-invokes the same function on its children.
2Passing an accumulated prefix down the call stack lets each level draw its own indentation correctly.
3Sorting by a tuple key groups directories before files while keeping each group alphabetical.

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