Chez Dynamic

chez-dynamic is a collection of functions / syntax (macros) that aid in dynamic development when using Chez scheme.

Install and use

The supplied GNU Makefile will install to LIBDIR. The default location is ~/lib/csv.

LIBDIR must be in (library-directories) to be usable from Chez scheme.

eg,

$ make install

To override LIBDIR:

$ make LIBDIR=~/newlibdir install

To use from Chez scheme:

(import (dynamic))

reimport

reimport allows for reloading R6RS libraries in Chez scheme.

It is designed for use within the Chez REPL. Use in any other environments will involve adjusting the (current-environment) parameter.

reimport uses (library-search-handler) to find the source file only for a library. Future versions may include the ability to load shared object files via (load-shared-object).

Note that reimport uses eval to refresh bindings and must be used with caution. Please study the source code if using in public works.

Example

Create a library x such that it exists within (library-directories):

(library (x)
  (export val)
  (import (chezscheme))
 (define val 3))

Now import into a Chez repl:

> (import (x))

Edit the val define in the x library:

(define val 4)

And in the Chez REPL, reimport to see the new value:

> (reimport (x))
> val
4

Beware

reimport uses eval to recreate library bindings and so must be used with caution. It does that within current-environment.

case-import

Perform an import and subsequent defines based on the existance of a library.

Note that this function only checks for the existance of the library, and not whether it imports successfully.

example

This example shows how case-import could be used to define a set of bindings based on whether irregex or srfi :115 regexp bindings are available.

(case-import
 [(irregex)
 ...]
 [(srfi :115 regexp)
 ...])

current-environment

A parameter that defaults to interaction-environment. This is used by the eval in reimport.

License

Written by Akce and released into the public domain.