Replace "starred_list" with standard grammar term "expression_list" in for statement documentation

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In the compound statements docs, section 8.3 i found:

for_stmt ::= "for" target_list "in" starred_list ":" suite
["else" ":" suite]

However, starred_list does not appear to be a defined production rule elsewhere in the language reference. It seems to act more like a semantic placeholder to indicate that starred_expressions (like *x) are allowed in the iterable.

Since the real grammar uses expression_list — which already includes starred_expression — would it be more consistent and accurate to write this instead?:

for_stmt ::= "for" target_list "in" expression_list ":" suite
["else" ":" suite]

…and then note in the accompanying text that starred_expression is supported?
This might reduce confusion for readers trying to understand or implement the formal grammar.
Can I work on that?

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Hi, I am willing to work on this issue #134026
Assign me to this issue.

Hi, I am willing to work on this issue #134026 Assign me to this issue.

Hi, I actually opened this issue because I noticed the inconsistency and proposed the solution. I'm planning to submit a PR for it shortly. Appreciate the interest, but I’ll be taking this one. I asked in the issues because even i am not sure if its supposed to be changed or whether "starred_list" is correct. Im hoping for someone more experienced to help clarify it. I am new here too and this is my first doc inconsistency, I do not have the power to assign issues as thats only for trusted developers i believe

Got it, Thanks

See

cpython/Grammar/python.gram

Lines 715 to 723 in 6df3976

    
           star_expressions[expr_ty]: 
        
               | a=star_expression b=(',' c=star_expression { c })+ [','] { 
        
                   _PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_seq_insert_in_front(p, a, b)), Load, EXTRA) } 
        
               | a=star_expression ',' { _PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_singleton_seq(p, a)), Load, EXTRA) } 
        
               | star_expression 
        
           star_expression[expr_ty] (memo): 
        
               | '*' a=bitwise_or { _PyAST_Starred(a, Load, EXTRA) } 
        
               | expression

ah okay. Sorry to bother i must have missed it as i hit "starred" on my ctrl+f in the grammar. Thank you

No, you misunderstood. This is a quote from the grammar for your reference. I believe issue is valid.

No, you misunderstood. This is a quote from the grammar for your reference. I believe issue is valid.

oh okay.. its my first issue ever on github so am a bit nervous.
so i change the starred_list into star_expression?

so i change the starred_list into star_expression?

I'm not sure about naming. But whatever it will be, you should define the starred_list.

Oh okay. I will look into doing that

gh-134026: Fix grammar description of for statement (GH-134034)

pythongh-134026: Fix grammar description of for statement (pythonGH-1…

[3.14] gh-134026: Fix grammar description of for statement (GH-134034) (

pythongh-134026: Fix grammar description of for statement (pythonGH-1…

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Replace "starred_list" with standard grammar term "expression_list" in for statement documentation #134026

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	star_expressions[expr_ty]:
	\| a=star_expression b=(',' c=star_expression { c })+ [','] {
	_PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_seq_insert_in_front(p, a, b)), Load, EXTRA) }
	\| a=star_expression ',' { _PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_singleton_seq(p, a)), Load, EXTRA) }
	\| star_expression

	star_expression[expr_ty] (memo):
	\| '*' a=bitwise_or { _PyAST_Starred(a, Load, EXTRA) }
	\| expression

Replace "starred_list" with standard grammar term "expression_list" in for statement documentation #134026

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sanjai-11 commented on May 15, 2025

Yash-Vijay29 commented on May 15, 2025

sanjai-11 commented on May 15, 2025

skirpichev commented on May 15, 2025

Yash-Vijay29 commented on May 15, 2025

skirpichev commented on May 15, 2025

Yash-Vijay29 commented on May 15, 2025

skirpichev commented on May 15, 2025

Yash-Vijay29 commented on May 15, 2025

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