[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Axiom-developer] "has" and "with" (was curious algebra failure)
From: |
Gabriel Dos Reis |
Subject: |
Re: [Axiom-developer] "has" and "with" (was curious algebra failure) |
Date: |
Mon, 13 Aug 2007 12:06:16 -0500 (CDT) |
On Mon, 13 Aug 2007, Bill Page wrote:
| On 13 Aug 2007 00:39:45 -0500, Gabriel Dos Reis wrote:
| > ...
| > 2. When one defines a category with default implementation, like
| > Monad, the compiler extracts the "purely categorial" part of
| > Monad, e.g. the exports; then it implicitly creates a package
| > Monad& with an implicit parameter S of type Monad. E.g., it is
| > as if the code was written:
| >
| > )abbrev package MONAD- Monad&
| > Monad&(S: Monad): Public == Private where
| > Public ==> with
| > "**" : (S, PositiveInteger) -> S
| >
| > Private ==> add
| > import RepeatedSquare(S)
| > x ** n == expt(x, n)
| >
| >
| > Now the compiler goes on typecheking the defnition x ** n.
| > It sees the use of expt() and find out that the only expt() in
| > scope if the one from RepeatedSquare(S). Then it tries
| > to instantiate that package -- just like a function call.
| > From there, it applies the usual rules: Can I coerce S of
| > type Monad to the expected argument type of RepeatedSquare()?
| > They answer comes out as "no". Hence the error.
| >
| > Is that less confusing?
| >
|
| Yes, thank you! But of course that is how packages and domains in Spad
| are normally written and this package does in fact compile just fine
| in Spad. See:
|
| http://wiki.axiom-developer.org/SandBoxMonad
|
| as it should.
|
| The question of coercing Monad to
|
| SetCategory with "*": (%, %) -> %
|
| must be yes.
A question is "why must it be `yes'"?
| I guess the question still is how? and why? does it work.
Indeed.
-- Gaby
- Re: [Axiom-developer] "has" and "with" (was curious algebra failure), (continued)
- Re: [Axiom-developer] "has" and "with" (was curious algebra failure), Ralf Hemmecke, 2007/08/13
- [Axiom-developer] "has" and "with" and bug, Ralf Hemmecke, 2007/08/13
- Re: [Axiom-developer] "has" and "with" and bug, William Sit, 2007/08/13
- Re: [Axiom-developer] "has" and "with" and bug, Ralf Hemmecke, 2007/08/13
- [Axiom-developer] Re: "has" and "with" and bug, Gabriel Dos Reis, 2007/08/13
- Re: [Axiom-developer] "has" and "with" (was curious algebra failure), Gabriel Dos Reis, 2007/08/13
- Re: [Axiom-developer] "has" and "with" (was curious algebra failure), Bill Page, 2007/08/13
- Re: [Axiom-developer] "has" and "with" (was curious algebra failure),
Gabriel Dos Reis <=
- Re: [Axiom-developer] "has" and "with" (was curious algebra failure), Ralf Hemmecke, 2007/08/13
- Re: [Axiom-developer] "has" and "with" (was curious algebra failure), Gabriel Dos Reis, 2007/08/13
- Re: [Axiom-developer] "has" and "with", Ralf Hemmecke, 2007/08/16
- Re: [Axiom-developer] "has" and "with", Gabriel Dos Reis, 2007/08/16
- Re: [Axiom-developer] "has" and "with", Ralf Hemmecke, 2007/08/16
- Re: [Axiom-developer] "has" and "with", Gabriel Dos Reis, 2007/08/16
- Re: [Axiom-developer] "has" and "with", Ralf Hemmecke, 2007/08/16
- Re: [Axiom-developer] "has" and "with", Gabriel Dos Reis, 2007/08/16
- Re: [Axiom-developer] "has" and "with", Ralf Hemmecke, 2007/08/16
- Re: [Axiom-developer] "has" and "with", Gabriel Dos Reis, 2007/08/16