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Missing indentation after if

🐛 Fix the bug Topic: strings Difficulty: easy Free

What this problem practises

Python strings are immutable sequences. "Fixing" a string always produces a new one, so the return value has to be captured; slicing rules apply, and every method — upper(), strip(), split(), join() — behaves differently from the in-place mutation you might be picturing.

This is a fix-the-bug problem: a short program is given in its broken state, and the task is to repair the code so it produces the required output. The interactive editor runs your fixed version in the browser and checks it for you — no setup, no local interpreter.

Difficulty: easy — the fix or the trick is normally a single line, and a careful read should be enough.

The challenge

This should check if a string is empty and print a message, but it crashes instead. Fix it.

The code runs in PyDebug’s in-browser compiler. Open the problem, run the snippet, watch the exact error or output, and keep iterating until it is right. Signed-in solves count toward XP and your daily streak.

The error it raises

Run the broken snippet and Python stops with this exact error: IndentationError: expected an indented block. Match it to the Python errors guide, then repair the line that produced it — knowing the message is half the fix.

The snippet

The interactive editor pre-fills exactly this code, broken and ready to repair:

name = ""
if name == "":
print("Name is empty")
else:
    print("Hello", name)

Understand the rule

After a header line ending in a colon, Python requires the next statement to be indented — indentation is the block syntax, not styling. Write if x > 5: and put the next line at the same level, and the parser stops with IndentationError: expected an indented block. Nothing has run yet; this is a structure problem, not a logic problem.

How to trace it

The error names the line after the header: that line needed to be pushed right.
Indent every statement that belongs inside the if by one consistent level (4 spaces is the convention).
Check the block's end: the first line back at the old indentation is the first line outside the if.
If the body is intentionally empty for now, write pass as a placeholder — an empty block is illegal.

Common wrong fixes

Mixing tabs and spaces so lines look aligned in the editor but differ to the parser (TabError).
Indenting only the first statement of an intended multi-line body, silently moving the rest outside the if.
Adding braces or keywords like end out of habit from other languages; indentation alone defines the block.

Rule to remember

A colon promises a block, and the block must be indented — consistently, in spaces. Use pass when a body is intentionally empty, and never mix tabs with spaces.

Solve it in the interactive editor →

🐍 Learning path: Python Basics

Problem 2 of 12 in this path. Work them in order — each one builds on the rule before it.

← Wrong quote type breaks the string Next in path: Inconsistent indentation →

Keep going

Python debugging guide — a systematic method for finding bugs like this one fast.
Browse every strings problem in this topic.
Common Python errors and what they actually mean, plus the Python glossary for any term used on this page.