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[ty] fix mdtest prose about string literal identity checks #27639

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carljm merged 1 commit into from
Aug 10, 2026
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[ty] fix mdtest prose about string literal identity checks #27639

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6 changes: 3 additions & 3 deletions crates/ty_python_semantic/resources/mdtest/narrow/conditionals/is.md
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Expand Up @@ -538,9 +538,9 @@ def literal_string(value: object, text: LiteralString) -> None:
reveal_type(value) # revealed: LiteralString
```

A string without known literal origin can have the same runtime value as an excluded string literal.
Identity preserves the existing origin exclusion instead of making the successful branch
unreachable.
The same string object (same memory address) can be referenced by multiple different expressions
(due to aliasing or interning). Some of those expressions may be validly typed as having literal
origin and others may not. Checking string identity does not assume this is impossible:

```py
def negated_string_literal(value: Not[Literal["hello"]]) -> None:
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