[bitc-dev] define, deftype

[Jonathan S. Shapiro]

On Tue, 2005-01-18 at 15:57 -0500, Mark Miller wrote:
> Jonathan S. Shapiro wrote:
> > The rule for DEFINE is now that DEFINE takes the form:
> > 
> > 	(define <pattern> <expression>)
> > [...]
> > We then decided that DEFINE should be LETREC-like. [...]
> 
> Btw, these suggestions were based on the E define-expr
> http://www.erights.org/elang/blocks/defVar.html
> 
> 
> >   2. For each sub-expression that unifies with some
> >      free variable in the pattern, either
> >        (a) the expression is a lambda form, or
> >        (b) no free variable in the expression
> >            is also free in the pattern.
> 
> (b) should be
> 
>      no free variable in the expression is also defined in the pattern.

These statements are equivalent, since pattern syntax does not permit
shadowing identifiers.

shap