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0 pointsom21y ago0 comments

What’s the difference between a union type and a disjoint union type? In that C# proposal I couldn’t tell which syntax was which branch of your dichotomy.

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noelwelsh1y ago

disjoint union is sum type / enum / algebraic data type. Defined at the point of declaration. Each case is distinct (hence, disjoint)

union is what Typescript has. Defined at the point of use. Cases need not be distinct.

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0 pointsom21y ago0 comments

What’s the difference between a union type and a disjoint union type? In that C# proposal I couldn’t tell which syntax was which branch of your dichotomy.

0 comments

noelwelsh1y ago

disjoint union is sum type / enum / algebraic data type. Defined at the point of declaration. Each case is distinct (hence, disjoint)

union is what Typescript has. Defined at the point of use. Cases need not be distinct.

j / k navigate · click thread line to collapse