#Personal Use files Just some random

Backtrace Tool

Quick call tracer for debugging. Shows what functions called what and where exceptions happened.

Basic Usage

from backtrace import trace_calls

# Decorator - shows trace every time
@trace_calls()
def my_function():
    helper()
    another_helper()
    return result

# Only show trace on errors
@trace_calls(trace_on_success=False)
def risky_stuff():
    # Only outputs if this crashes
    return do_something()

# Write to file instead of console
@trace_calls(log_file="debug.log")
def production_code():
    return process()

# Plain text (no colors/formatting)
@trace_calls(use_rich=False)
def simple_output():
    return calc()

What You'll See

Success:

• Green box with tree showing function calls
• ↳ = entering function (shows line number where it was called)
• ↰ = exiting function

Handled Exception:

• Green box, says "exception handled"
• ⚠ = exception happened but was caught

Unhandled Exception:

• Red box showing the error
• ✗ = where the exception occurred
• Still raises the exception normally

Notes

• Only traces your code (filters out pandas, numpy, stdlib, etc.)
• Shows where functions are called from, not where they're defined
• Zero performance impact when not using the decorator