Custom Query (1630 matches)

The following program refuses to run or compile:

(import srfi-88)
;(import (chicken keyword)) ;; this works

(print (string->keyword "foo"))

This is about making it possible for egg authors to specify the minimum version of CHICKEN required for their eggs in egg files.

Something like

(minimum-required-chicken-version "5.5.0")

When users try to install eggs, chicken-install should verify whether the version of CHICKEN is recent enough to install the requested eggs.

This gives us more flexibility for making not-so-radical-but-breaking core API changes within a major CHICKEN version, still providing good feedback to users.

User "kluk" brought up on IRC that it would be nice to have line number information in the interpreter, for better error reporting. This is somewhat problematic because the interpreter has to deal with potentially unbounded input, as one can reload files interactively or have code be evaled at will.

Perhaps a relatively simple solution would be to use a weak hash table for the line number database.

Since we already *have* weak pairs in core, perhaps we should simply expose these to the user (and csi).

We could use this API from MIT Scheme:

​https://web.mit.edu/scheme_v9.2/doc/mit-scheme-ref/Weak-Pairs.html

Also in Chez Scheme:

​https://cisco.github.io/ChezScheme/csug9.5/smgmt.html#./smgmt:h2

Then this could form the basis of a weak hash table API as well. Perhaps best left as an internal API (just like other compiler hash tables are also internal). Later someone(TM) can provide an egg with a proper weak hash table API.

We should probably also look seriously into ephemerons (a la ​https://srfi.schemers.org/srfi-124/srfi-124.html), but from ​https://scheme-48.s48.narkive.com/YJq3GJOw/ephemerons-long-message-with-a-brief-preamble it seems these are somewhat trickier to implement, so that might be for a later version.