Add intersection (A & B), union (|), and grouping ([...]) type syntax - #1231

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apiology:fix-1229-intersection-types

Commits on Jul 30, 2026

Give RBS intersection types (A & B) real intersection semantics

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8966409
Rename PR #1119's intersect_with to narrow_with to avoid name collision

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f85e823
Fix duck-typed conjuncts inside an expected intersection

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53f7b1b
Drop issue-URL comments that only restate what git log already shows

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822d2f9
Generalize Intersection#conjuncts to hold ComplexTypes, not UniqueTypes

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8c8312a

Commits on Jul 31, 2026

Build an intersection instead of discarding a mix-in narrowing

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7af1bb4
Build every composite RBS type as an object, not a joined string

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4a61e0e
Fix an intersection failing to conform to itself

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0d5b356

Commits on Aug 1, 2026

Add | union and [...] grouping operators, matching YARD #1700

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5e6f8ba

Commits on Aug 6, 2026

Add pending specs for two intersection-type bugs (#1231)

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eedf506
Expand intersection-type corner-case coverage from PR #1231 review

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0136044
Document root cause and #1266 dependency for the Hash#fetch leak

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3c30a84
Document which pending specs are #1266-dependent vs independent

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2bb0a15
Fix method-call resolution on intersection-typed receivers (#1231)

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342b11b
Add pending spec for strict-union call resolution bug

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76181ad
Add pending spec proving the Hash dispatch bug is union-general

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8935e12
Fix order-dependent Hash intersection dispatch (partial, #1231)

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7adb5db