Re: The point of 'provide'

On Sun, Jan 03, 2010 at 02:18:09PM -0500, John Cowan wrote:

Hi John,

Thanks for your very detailed answer!

> That is because 'use' does a 'require' (which calls 'provided?', and
> if it returns #f, calls 'load').  If you define the module in this way,
> you want to use 'import' rather than 'use'.

My goal here is to load a file regardless of whether it was loaded by
some bootstrap code or installed as an extension.

Is there a way to do this programmatically?

> There's a bug here, as shown by the traceback:
> 
> (##core#begin (##sys#require (quote foo)) (import foo))
> 
> This is an attempt to require *and then* import, but it cannot work,
> because import is a macro and does its work at macroexpansion time,
> whereas ##sys#require is a procedure and does its work at runtime.

Ah, it finally makes sense why this is going wrong.  I was put on the
wrong track by the error I got.

Cheers,
Peter
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