union type syntax

Waldemar Horwat waldemar at google.com
Fri Mar 21 15:46:14 PDT 2008


There is no solid technical reason for requiring parentheses here.  They're here because of people's preferences.  I don't find them particularly useful here.

    Waldemar


Peter Hall wrote:
> Now that union type uses "|" instead of "," for the delimiter, could
> the parentheses be made optional? It seems like parentheses are used
> elsewhere only for grouping and function calls/definitions.
> 
>     UnionType ::=  Type ( "|" UnionType )?
> 
> which should be easily distinguishable from a bitwise OR expression.



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