--- title: "Python Internals - Exploring Chained Comparison Operators" url: https://daily.dev/posts/python-internals---exploring-chained-comparison-operators-o0yxf5hrw source_url: https://arpitbhayani.me/blogs/chained-operators-python type: article source: "Arpit Bhayani" published: 2026-05-31T07:55:06.113Z updated: 2026-05-31T09:22:21.117Z tags: ["python", "cpython"] reading_time: 10 upvotes: 0 comments: 0 language: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Python Internals - Exploring Chained Comparison Operators **[Arpit Bhayani](https://daily.dev/sources/arpit-bhayani)** · 10 min read · 0 upvotes · 0 comments ## Summary Python supports chained comparison operators like `a < b < c`, evaluating them as `(a < b) and (b < c)` with short-circuit semantics — unlike C, which evaluates left-to-right using the result of each comparison as the next operand. Using Python's `dis` module, the bytecode for chained comparisons is dissected instruction by instruction, revealing how `DUP_TOP` and `ROT_THREE` preserve the middle operand, and how `JUMP_IF_FALSE_OR_POP` implements short-circuiting. The post then walks through modifying CPython's `compiler_compare` function in `compile.c` to remove those three instructions, making Python evaluate chained comparisons the C way — causing `-3 < -2 < -1` to return `False` instead of `True`. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Python Booleans and Boolean Expressions](https://daily.dev/posts/python-booleans-and-boolean-expressions-zodkkivgn) · Planet Python · 0 upvotes · 0 comments --- Tags: [#python](https://daily.dev/tags/python), [#cpython](https://daily.dev/tags/cpython) [View this post on daily.dev](https://daily.dev/posts/python-internals---exploring-chained-comparison-operators-o0yxf5hrw)