I was reading about Python’s execution model and came across something confusing. According to the official docs, a block in Python refers to code that gets executed as a single unit. The documentation specifically mentions that modules, function bodies, and class definitions are considered blocks.
This definition seems different from what I expected. I always thought that indented code sections like if statements or while loops would also be called blocks. But based on this description, it sounds like they might not qualify as proper blocks in Python.
Can someone help me understand what “executed as a unit” actually means in this context? Why wouldn’t something like a while loop body meet this criteria? Also, if indented code sections aren’t technically blocks, what terminology should I use to describe them instead?
It comes down to namespaces and how Python compiles code. When Python hits a module, function, or class definition, it creates a separate namespace and compiles that code into its own object. That’s what “executed as a unit” means - the whole block gets compiled together with its own local scope. Indented sections like if statements and while loops don’t create new namespaces. They share the same local variables as whatever function or module contains them. Python’s compiler treats them as part of the larger block they’re nested in, not as separate execution units. Python docs call these indented sections “suites” - just a group of statements controlled by something like if, while, or for. So yeah, they look like blocks with the indentation, but they’re not actually blocks in Python’s execution model.
You’re mixing up visual structure with how Python actually executes code. When Python hits a function definition, it creates a separate code object that runs independently with its own variable lookups. The interpreter compiles the whole function body into bytecode as one unit. While loops are just instructions that redirect execution flow within the current scope - totally different thing. Check any function’s code attribute and you’ll see the compiled bytecode for that execution unit. Control structures don’t get their own code objects because they’re part of the sequential instruction flow. Yeah, “suite” is technically correct for indented code under control statements, but most devs just say “code blocks” and don’t worry about the distinction.
totally get where ur coming from! python blocks r more about scope, like functions and classes, while loops or ifs just run in the same scope as where they’re defined, so they ain’t separate blocks. hope that clears it up!
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