Re: [Chicken-users] Understanding modules?

[Norman Gray]

John and all, hello.

On 22 May 2016, at 1:59, John Cowan wrote:

> It's also worth noting that use (or
> require-extension, which is the same thing) depends on the module 
> having
> the same name as the file.

Thanks: It did look as if that assumption was baked in somewhere; if the 
process _depends_ on the naming, then...

vvvv

A module may _export_ a subset of the bindings defined in its body, 
making those bindings visible to other code which _imports_ the module, 
at compilation time.  A module must be _loaded_ into a CHICKEN 
interpreter before its bindings can be imported; this loading can happen 
explicitly, or more commonly as a side-effect of some higher level 
expression, as below; this loading happens at run-time.  In CHICKEN, the 
loadable object can be either the Scheme source code in a `.scm` file, 
or a shared object compiled with `csc -shared`.

If, as is usually the case, you compile code which depends on other 
modules, then you must use an _import library_; this is generated by 
`csc` when given the option `-emit-all-import-libraries`.  In the most 
common case, a file foo.scm will contain a single (module foo ...) form, 
and the compilation should be done with `-emit-all-import-libraries`, 
which generates a file `foo.import.scm` named after the module.  If a 
module uses this naming pattern, then the expression `(use foo)` (or 
equivalently `(require-extension foo)`) will automatically handle 
finding and loading the library, and importing its symbols.

The `(module ...)` form is documented below.  See also the discussion of 
`require-extension` and `use` on 
<http://wiki.call-cc.org/man/4/Non-standard%20macros%20and%20special%20forms>, 
and possibly the discussion of `require` on 
<http://wiki.call-cc.org/man/4/Unit%20eval#loading-extension-libraries>

^^^^

Best wishes,

Norman


--
Norman Gray  :  https://nxg.me.uk
SUPA School of Physics and Astronomy, University of Glasgow, UK