On 07/25/2012 10:26 AM, Sam Tobin-Hochstadt wrote:
On Wed, Jul 25, 2012 at 9:29 AM, Neil Toronto <neil.toro...@gmail.com> wrote:
After thinking about it, I don't want an Immutable-Vector type, for which v
: Immutable-Vector proves (immutable? v) is #t. That would be seriously
annoying to users of a vector library.
What if TR had a notion of const-ness, like in C? Suppose (Vectorof A) is a
subtype of (Const-Vectorof B) when A is a subtype of B, and (Const-Vectorof
A) is never a subtype of (Vectorof B).
How exactly are these different? An immutable vector is a vector, but
could be covariant, which seems like what you want. However, a mutable
vector can't be treated as an immutable vector.
I don't want to tell Typed Racket "This vector's values never change." I
want to tell it "Code in this scope never changes this vector's values."
That's why I called it "const" instead of "immutable".
Neil ⊥
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