Re: getting started with guix import nix

[ludo@gnu.org (Ludovic Courtès)]

Hello!

Paul Garlick <pgarlick@tourbillion-technology.com> skribis:

> I am attempting to package the OpenCASCADE-OCE library for Guix using
> the Nix opencascade_oce package as a starting point.  I have a standard
> Guix installation, a standard Nix installation plus the Guix source to
> work on separately.  opencascade_oce is not installed in the Nix store.
>  The Nix setup is:
>
> $ echo $NIX_PATH
> nixpkgs=/home/paul/.nix-defexpr/channels/nixpkgs
>
> $ which nix-instantiate
> /home/paul/.nix-profile/bin/nix-instantiate
>
> I try:
>
> $ export NIX_REMOTE=daemon
> $ ./pre-inst-env guix import nix $HOME/.nix-defexpr/channels/nixpkgs
> opencascade_oce

You’re doing it right.  Here I get:

--8<---------------cut here---------------start------------->8---
$ NIX_REMOTE=daemon ./pre-inst-env guix import nix /data/src/nixpkgs/ opencascade_oce
;;; SSAX warning: Skipping PI: xml

trace: lib.zip is deprecated, use lib.zipAttrsWith instead
trace: `mkStrict' is obsolete; use `mkOverride 0' instead.
trace: `types.list' is deprecated; use `types.listOf' instead
;; converted from /data/src/nixpkgs/pkgs/development/libraries/opencascade/oce.nix:5

(package
  (name "opencascade-oce")
  (version "0.16")
  (source
    (origin
      (method url-fetch)
      (uri (string-append
             "https://github.com/tpaviot/oce/archive/OCE-"
             version
             ".tar.gz"))
      (sha256
        (base32
          "05bmg1cjz827bpq8s0hp96byirm4c3zc9vx26qz76kjsg8ry87w4"))))
  (build-system gnu-build-system)
  (inputs
    `(("cmake" ,cmake)
      ("freetype" ,freetype)
      ("ftgl" ,ftgl)
      ("qt" ,qt)
      ("libtool" ,libtool)
      ("libXmu" ,libXmu)
      ("file" ,file)
      ("tk" ,tk)
      ("tcl" ,tcl)
      ("mesa" ,mesa)))
  (home-page "http://www.opencascade.org/")
  (synopsis
    "Open CASCADE Technology, libraries for 3D modeling and numerical simulation")
  (description #f)
  (license #f))
$ git describe
v0.11.0-3412-ge8a463e
$ (cd /data/src/nixpkgs/ ; git describe)
release-16.03-start-8750-gdde259d
--8<---------------cut here---------------end--------------->8---

> i get:
>
> ;;; SSAX warning: Skipping PI: xml
>
> trace: lib.zip is deprecated, use lib.zipAttrsWith instead
> trace: `mkStrict' is obsolete; use `mkOverride 0' instead.
> Backtrace:
> In guix/import/snix.scm:
>  190: 19 [loop #<input: #{read pipe}# 10> () #f (() . #<vhash 1c6c320 5
> pairs>)]
>  190: 18 [loop #<input: #{read pipe}# 10> () ...]
>  190: 17 [loop #<input: #{read pipe}# 10> () #f (() . #<vhash 1c6c320 5
> pairs>)]
>  190: 16 [loop #<input: #{read pipe}# 10> () ...]
>  190: 15 [loop #<input: #{read pipe}# 10> () #f (() . #<vhash 1c6c320 5
> pairs>)]
>  190: 14 [loop #<input: #{read pipe}# 10> () ...]
>  190: 13 [loop #<input: #{read pipe}# 10> () #f (() . #<vhash 1c6c320 5
> pairs>)]
>  190: 12 [loop #<input: #{read pipe}# 10> () ...]
>  190: 11 [loop #<input: #{read pipe}# 10> () #f (() . #<vhash 1c6c320 5
> pairs>)]
>  190: 10 [loop #<input: #{read pipe}# 10> () ...]
>  190: 9 [loop #<input: #{read pipe}# 10> () #f (() . #<vhash 1c6c320 5
> pairs>)]
>  190: 8 [loop #<input: #{read pipe}# 10> () #f (() . #<vhash 1c6c320 5
> pairs>)]
>  190: 7 [loop #<input: #{read pipe}# 10> () #f (() . #<vhash 1c6c320 5
> pairs>)]
>  190: 6 [handle-start-tag function #<input: #{read pipe}# 10> ...]
> In sxml/upstream/SSAX.scm:
> 1523: 5 [#<procedure fda8a0 at sxml/upstream/SSAX.scm:1522:1 (tag-head
> port elems entities namespaces)> function ...]
> 1246: 4 [#<procedure 16e2800 at sxml/upstream/SSAX.scm:1233:2 (port
> entities)> #<input: #{read pipe}# 10> ...]
> 1190: 3 [read-attrib-value #\" #<input: #{read pipe}# 10> () ()]
> In sxml/ssax/input-parse.scm:
>  103: 2 [next-token () (#\" #\space #\newline ...) ...]
> In ice-9/rdelim.scm:
>   88: 1 [read-delimited "\" \n\t\r<&" #<input: #{read pipe}# 10> peek]
> In unknown file:
>    ?: 0 [%read-delimited! "\" \n\t\r<&" ...]
>
> ERROR: In procedure %read-delimited!:
> ERROR: Throw to key `vm-error' with args `(vm-run "VM: Stack overflow"

It may be that we’re not getting the same XML output from
‘nix-instantiate’ and that somehow confuses the XML parser in your case.

To investigate, you’d need to run the same ‘nix-instantiate’ command
that snix.scm invokes, same its XML output, and then try parsing it with
‘xml->sxml’ from (sxml simple).

HTH!

Ludo’.