gexp: Add 'ungexp-native' and 'ungexp-native-splicing'.

* guix/gexp.scm (<gexp>)[natives]: New field.
  (write-gexp): Use both 'gexp-references' and
  'gexp-native-references'.
  (gexp->derivation): Use both 'gexp-inputs' and 'gexp-native-inputs',
  and append them.
  (gexp-inputs): Add 'references' parameter and honor it.
  (gexp-native-inputs): New procedure.
  (gexp->sexp)[reference->sexp]: Add 'native?' parameter and honor it.
  Use it, and use 'gexp-native-references'.
  (gexp)[collect-native-escapes]: New procedure.
  [escape->ref]: Handle 'ungexp-native' and 'ungexp-native-splicing'.
  [substitute-ungexp, substitute-ungexp-splicing]: New procedures.
  [substitute-references]: Use them, and handle 'ungexp-native' and
  'ungexp-native-splicing'.
  Adjust generated 'make-gexp' call to provide both normal references
  and native references.
  [read-ungexp]: Support 'ungexp-native' and
  'ungexp-native-splicing'.
  Add reader extension for #+.
* tests/gexp.scm (gexp-native-inputs): New procedure.
  (gexp->sexp*): Add 'target' parameter.
  ("ungexp + ungexp-native",
  "input list + ungexp-native",
  "input list splicing + ungexp-native-splicing",
  "gexp->derivation, ungexp-native",
  "gexp->derivation, ungexp + ungexp-native"): New tests.
  ("sugar"): Add tests for #+ and #+@.
* doc/guix.texi (G-Expressions): Document 'ungexp-native' et al.

1 files changed, 5 insertions, 4 deletions

diff --git a/.dir-locals.el b/.dir-locals.el
index 69c25cbe8f..ce7033757d 100644
--- a/.dir-locals.el
+++ b/.dir-locals.el
@@ -40,11 +40,12 @@
    (eval . (put 'mlet 'scheme-indent-function 2))
    (eval . (put 'run-with-store 'scheme-indent-function 1))
 
-   ;; Recognize '~' and '$', as used for gexps, as quotation symbols.  This
-   ;; notably allows '(' in Paredit to not insert a space when the preceding
-   ;; symbol is one of these.
+   ;; Recognize '~', '+', and '$', as used for gexps, as quotation symbols.
+   ;; This notably allows '(' in Paredit to not insert a space when the
+   ;; preceding symbol is one of these.
    (eval . (modify-syntax-entry ?~ "'"))
-   (eval . (modify-syntax-entry ?$ "'"))))
+   (eval . (modify-syntax-entry ?$ "'"))
+   (eval . (modify-syntax-entry ?+ "'"))))
  (emacs-lisp-mode . ((indent-tabs-mode . nil)))
  (texinfo-mode    . ((indent-tabs-mode . nil)
                      (fill-column . 72))))