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Mirrors > Home > MPE Home > Th. List > ciun | Structured version Visualization version GIF version |
Description: Extend class notation to include indexed union. Note: Historically (prior to 21-Oct-2005), set.mm used the notation ∪ 𝑥 ∈ 𝐴𝐵, with the same union symbol as cuni 4427. While that syntax was unambiguous, it did not allow for LALR parsing of the syntax constructions in set.mm. The new syntax uses a distinguished symbol ∪ instead of ∪ and does allow LALR parsing. Thanks to Peter Backes for suggesting this change. |
Ref | Expression |
---|---|
vx | setvar 𝑥 |
cA | class 𝐴 |
cB | class 𝐵 |
Ref | Expression |
---|---|
ciun | class ∪ 𝑥 ∈ 𝐴 𝐵 |
Colors of variables: wff setvar class |
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