records: 'match-record' checks fields at macro-expansion time.

This allows 'match-record' to be more efficient (field offsets are
computed at compilation time) and to report unknown fields at
macro-expansion time.

* guix/records.scm (map-fields): New macro.
(define-record-type*)[rtd-identifier]: New procedure.
Define TYPE as a macro and use a separate identifier for the RTD.
(lookup-field, match-record-inner): New macros.
(match-record): Rewrite in terms of 'match-error-inner'.
* tests/records.scm ("match-record, simple")
("match-record, unknown field"): New tests.
* gnu/services/cuirass.scm (cuirass-shepherd-service): Rename 'log-file'
local variable to 'main-log-file'.
* gnu/services/getmail.scm (serialize-getmail-configuration-file): Move
after <getmail-configuration-file> definition.

1 files changed, 33 insertions, 0 deletions

diff --git a/tests/records.scm b/tests/records.scm
index 00c58b0736..8504c8d5a5 100644
--- a/tests/records.scm
+++ b/tests/records.scm
@@ -528,4 +528,37 @@ Description: 1st line,
                  '("a" "b" "c")
                  '("a")))
 
+(test-equal "match-record, simple"
+  '((1 2) (a b))
+  (let ()
+    (define-record-type* <foo> foo make-foo
+      foo?
+      (first  foo-first (default 1))
+      (second foo-second))
+
+    (list (match-record (foo (second 2)) <foo>
+            (first second)
+            (list first second))
+          (match-record (foo (first 'a) (second 'b)) <foo>
+            (second first)
+            (list first second)))))
+
+(test-equal "match-record, unknown field"
+  'syntax-error
+  (catch 'syntax-error
+    (lambda ()
+      (eval '(begin
+               (use-modules (guix records))
+
+               (define-record-type* <foo> foo make-foo
+                 foo?
+                 (first  foo-first (default 1))
+                 (second foo-second))
+
+               (match-record (foo (second 2)) <foo>
+                 (one two)
+                 #f))
+            (make-fresh-user-module)))
+    (lambda (key . args) key)))
+
 (test-end)