Assignment Expressions

E256161

Python language feature expression construct

Assignment Expressions are a Python language feature introduced by PEP 572 that allow assigning values to variables as part of larger expressions using the “walrus” operator (:=).

Try in SPARQL Jump to: Surface forms Disambiguation Statements Elicitation Referenced by

All labels observed (3)

Label	Occurrences
Assignment Expressions canonical	1
Python Language Reference – Expressions – Assignment expressions	1
walrus operator	1

How this entity was disambiguated

This entity first appeared as the object of triple T2321019 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.

NED1 Entity disambiguation (via context triple) gpt-5-mini-2025-08-07

Target entity: Assignment Expressions
Context triple: [PEP 572, title, Assignment Expressions]

A. Data Analysis Expressions
Data Analysis Expressions is a formula and query language used in Microsoft Power BI, Excel, and other Microsoft BI tools to create custom calculations and analyze data in tabular models.
B. operator grammar
Operator grammar is a formal linguistic framework developed by Zellig Harris that analyzes sentence structure through algebraic-like operations on strings rather than traditional phrase-structure rules.
C. SETSqx
SETSqx is a hybrid electronic trading service on the London Stock Exchange that combines periodic auctions with continuous quote-driven market making for less liquid securities.
D. ASM
ASM is the three-letter ISO 3166-1 alpha-3 country code assigned to American Samoa, an unincorporated territory of the United States in the South Pacific Ocean.
E. ASM
ASM is a leading professional organization dedicated to advancing the microbial sciences through research, education, and advocacy.
F. None of above. chosen
G. Unsure - the case is ambiguous/there is not enough information to decide.

NED2 Entity disambiguation (via description) gpt-5-mini-2025-08-07

Target entity: Assignment Expressions
Target entity description: Assignment Expressions are a Python language feature introduced by PEP 572 that allow assigning values to variables as part of larger expressions using the “walrus” operator (:=).

A. Data Analysis Expressions
Data Analysis Expressions is a formula and query language used in Microsoft Power BI, Excel, and other Microsoft BI tools to create custom calculations and analyze data in tabular models.
B. operator grammar
Operator grammar is a formal linguistic framework developed by Zellig Harris that analyzes sentence structure through algebraic-like operations on strings rather than traditional phrase-structure rules.
C. SETLX
SETLX is a modern, open-source programming language designed for teaching and experimenting with set theory and mathematical concepts through executable code.
D. SETSqx
SETSqx is a hybrid electronic trading service on the London Stock Exchange that combines periodic auctions with continuous quote-driven market making for less liquid securities.
E. ASM
ASM is the three-letter ISO 3166-1 alpha-3 country code assigned to American Samoa, an unincorporated territory of the United States in the South Pacific Ocean.
F. None of above. chosen

Statements (43)

Predicate	Object
instanceOf	Python language feature ⓘ expression construct ⓘ
alsoKnownAs	walrus operator ⓘ linked to: Assignment Expressions walrus operator (:=) ⓘ linked to: PEP 572
author	Chris Angelico ⓘ
bdfLDecisionBy	Guido van Rossum ⓘ
bindingTime	at runtime during expression evaluation ⓘ
canBeUsedIn	comprehensions ⓘ generator expressions ⓘ if statements ⓘ lambda expressions (with restrictions) ⓘ while statements ⓘ
cannotTarget	attribute references in some contexts (subject to normal assignment rules) ⓘ
category	Python expression syntax ⓘ
controversy	PEP 572 sparked significant discussion in the Python community ⓘ linked to: PEP 572
designGoal	avoid repeated expensive computations ⓘ improve readability in some patterns ⓘ
documentationSection	Python Language Reference – Expressions – Assignment expressions ⓘ linked to: Assignment Expressions
enables	inline assignment ⓘ reusing computed values within an expression ⓘ
evaluationOrder	expression on right of := is evaluated then bound to target name ⓘ
example	if (n := len(items)) > 0: print(n) ⓘ results = [y for x in data if (y := f(x)) is not None] ⓘ while (line := file.readline()) != "": process(line) ⓘ
exampleUseCase	capturing match results from regular expressions ⓘ filtering and binding in list comprehensions ⓘ reading input in a while loop ⓘ
introducedBy	PEP 572 ⓘ
introducedInVersion	Python 3.8 ⓘ
language	Python ⓘ
notAllowedIn	simple assignment target list ⓘ top-level of comprehension iterable expression (to avoid scoping confusion) ⓘ
pepNumber	572 ⓘ
purpose	assign values as part of larger expressions ⓘ
reduces	need for separate assignment statements ⓘ
relatedTo	assignment statements ⓘ name binding ⓘ
returns	assigned value ⓘ
scopeRule	follows normal Python scoping rules for the target name ⓘ
standardizedIn	Python 3 language specification ⓘ
status	accepted PEP ⓘ
syntaxForm	NAME := expression ⓘ
usesOperator	:= ⓘ

How these facts were elicited

Referenced by (3)

Full triples — surface form annotated when it differs from this entity's canonical label.

PEP 572 → title → Assignment Expressions ⓘ

Assignment Expressions → alsoKnownAs → walrus operator ⓘ

linked to: Assignment Expressions

Assignment Expressions → documentationSection → Python Language Reference – Expressions – Assignment expressions ⓘ