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Re: Q: Symbol optional in keyword parameter definition?
Roland Paterson-Jones rolandpj@bigfoot.com on 2001-06-25 10:00 wrote:
> The BNF for dylan in "The Dylan Reference Manual", p. 426, describes a
> keyword parameter as:
>
> keyword-parameter:
> SYMBOL(opt) variable default(opt)
>
> i.e. the keyword symbol is optional(?).
>
> What does it mean when you define a method such as:
>
> define method m( req1, req2, req3, #key key1 ) ...
>
> where key1 is a keyword parameter with no associated keyword symbol? How can
> key1 be bound and used?
The key defaults to being the name of the variable. You are permitted to
specify a key that is different from the variable. Handy when the key name
is a reserved word (which would not be permitted as a variable name).
References: