04/08: records: Make a couple of procedures available at expansion time.

[Ludovic Courtès]

civodul pushed a commit to branch master
in repository guix.

commit 9768848af80764af6040e75867ae15a41228364b
Author: Ludovic Courtès <address@hidden>
Date:   Thu May 31 17:32:22 2018 +0200

    records: Make a couple of procedures available at expansion time.
    
    * guix/records.scm (current-abi-identifier, abi-check): Wrap in
    'eval-when'.
---
 guix/records.scm | 31 +++++++++++++++++--------------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/guix/records.scm b/guix/records.scm
index c71cfcf..da3ecda 100644
--- a/guix/records.scm
+++ b/guix/records.scm
@@ -63,22 +63,25 @@
 (set-exception-printer! 'record-abi-mismatch-error
                         print-record-abi-mismatch-error)
 
-(define (current-abi-identifier type)
-  "Return an identifier unhygienically derived from TYPE for use as its
+(eval-when (expand load eval)
+  ;; The procedures below are needed both at run time and at expansion time.
+
+  (define (current-abi-identifier type)
+    "Return an identifier unhygienically derived from TYPE for use as its
 \"current ABI\" variable."
-  (let ((type-name (syntax->datum type)))
-    (datum->syntax
-     type
-     (string->symbol
-      (string-append "% " (symbol->string type-name)
-                     " abi-cookie")))))
-
-(define (abi-check type cookie)
-  "Return syntax that checks that the current \"application binary
+    (let ((type-name (syntax->datum type)))
+      (datum->syntax
+       type
+       (string->symbol
+        (string-append "% " (symbol->string type-name)
+                       " abi-cookie")))))
+
+  (define (abi-check type cookie)
+    "Return syntax that checks that the current \"application binary
 interface\" (ABI) for TYPE is equal to COOKIE."
-  (with-syntax ((current-abi (current-abi-identifier type)))
-    #`(unless (eq? current-abi #,cookie)
-        (throw 'record-abi-mismatch-error #,type))))
+    (with-syntax ((current-abi (current-abi-identifier type)))
+      #`(unless (eq? current-abi #,cookie)
+          (throw 'record-abi-mismatch-error #,type)))))
 
 (define-syntax make-syntactic-constructor
   (syntax-rules ()