python · Python
The message
IndentationError: unexpected indent
What it means
The line is indented further than the one before it, and nothing above it opened a block that would justify the extra level. Usually you pasted code that carried its own leading spaces, or you deleted an if line and left its body indented under nothing. Remove the leading whitespace on the line the error points at; if you cannot see the difference, print that line through cat -A and the spaces and tabs become visible.
The fix
There is no one-line command for this. The explanation says what to look at instead.
- Printed by
- python
- Python
- 18
A Python traceback splits the answer in two — the last line says what went wrong, the frames above it say where — so reading only the last line gives you the name and loses the place, and for the value-is-missing errors such as NoneType and KeyError the cause almost always sits in a frame above the one that crashed.
Reading an error message
- Read from the first line down. The lower you go the more it is about the tool’s internals; the cause is usually at the top.
- If there is a file and a line number, start there — not the top stack frame, but the topmost line that names a file you wrote.
- Search the message verbatim, but strip your own paths and variable names first; those are what stop the search from matching.
- The same condition is worded differently across tool versions. If results look wrong, add the version number to the query.
- Before pasting a fix, check what it throws away. Some of these cannot be undone.
Common questions
Q. What does “IndentationError: unexpected indent” mean?
The line is indented further than the one before it, and nothing above it opened a block that would justify the extra level. Usually you pasted code that carried its own leading spaces, or you deleted an if line and left its body indented under nothing. Remove the leading whitespace on the line the error points at; if you cannot see the difference, print that line through cat -A and the spaces and tabs become visible.
Q. How do I fix it?
There is no one-line command. The explanation above says what to look at instead.
Q. Which tool prints this?
python. It sits under Python, and the message runs to 3 words.