import: opam: Add more patterns to opam file parser.

* guix/import/opam.scm: Add more patterns to peg parser.
(choice-pat choice condition-not condition-paren): New patterns.
(ground-value condition-content condition-var): Update patterns.

guix/import/opam.scm

@@ -58,7 +58,12 @@
 (define-peg-pattern weird-record all (and key (* SP) dict))
 (define-peg-pattern key body (+ (or (range #\a #\z) "-")))
 (define-peg-pattern value body (and (or conditional-value ground-value operator) (* SP)))
-(define-peg-pattern ground-value body (and (or multiline-string string-pat list-pat var) (* SP)))
+(define-peg-pattern choice-pat all (and (ignore "(") (* SP) choice (* SP)  (ignore ")")))
+(define-peg-pattern choice body
+  (or (and (or conditional-value ground-value) (* SP) (ignore "|") (* SP) choice)
+      conditional-value
+      ground-value))
+(define-peg-pattern ground-value body (and (or multiline-string string-pat choice-pat list-pat var) (* SP)))
 (define-peg-pattern conditional-value all (and ground-value (* SP) condition))
 (define-peg-pattern string-pat all (and QUOTE (* STRCHR) QUOTE))
 (define-peg-pattern list-pat all (and (ignore "[") (* SP) (* (and value (* SP))) (ignore "]")))
@@ -80,7 +85,8 @@
 (define-peg-pattern condition-form2 body
                     (and (* SP) (or condition-greater-or-equal condition-greater
                                     condition-lower-or-equal condition-lower
-                                    condition-neq condition-eq condition-content) (* SP)))
+                                    condition-neq condition-eq condition-not
+                                    condition-content) (* SP)))
 
 ;(define-peg-pattern condition-operator all (and (ignore operator) (* SP) condition-string))
 (define-peg-pattern condition-greater-or-equal all (and (ignore (and ">" "=")) (* SP) condition-string))
@@ -91,10 +97,12 @@
 (define-peg-pattern condition-or all (and condition-form2 (* SP) (ignore "|") (* SP) condition-form))
 (define-peg-pattern condition-eq all (and (? condition-content) (* SP) (ignore "=") (* SP) condition-content))
 (define-peg-pattern condition-neq all (and (? condition-content) (* SP) (ignore (and "!" "=")) (* SP) condition-content))
-(define-peg-pattern condition-content body (or condition-string condition-var))
+(define-peg-pattern condition-not all (and (ignore (and "!")) (* SP) condition-content))
+(define-peg-pattern condition-content body (or condition-paren condition-string condition-var))
 (define-peg-pattern condition-content2 body (and condition-content (* SP) (not-followed-by (or "&" "=" "!"))))
+(define-peg-pattern condition-paren body (and "(" condition-form ")"))
 (define-peg-pattern condition-string all (and QUOTE (* STRCHR) QUOTE))
-(define-peg-pattern condition-var all (+ (or (range #\a #\z) "-")))
+(define-peg-pattern condition-var all (+ (or (range #\a #\z) "-" ":")))
 
 (define (get-opam-repository)
   "Update or fetch the latest version of the opam repository and return the
@@ -171,18 +179,24 @@ path to the repository."
 (define (dependency->input dependency)
   (match dependency
     (('string-pat str) str)
+    ;; Arbitrary select the first dependency
+    (('choice-pat choice ...) (dependency->input (car choice)))
     (('conditional-value val condition)
      (if (native? condition) "" (dependency->input val)))))
 
 (define (dependency->native-input dependency)
   (match dependency
     (('string-pat str) "")
+    ;; Arbitrary select the first dependency
+    (('choice-pat choice ...) (dependency->input (car choice)))
     (('conditional-value val condition)
      (if (native? condition) (dependency->input val) ""))))
 
 (define (dependency->name dependency)
   (match dependency
     (('string-pat str) str)
+    ;; Arbitrary select the first dependency
+    (('choice-pat choice ...) (dependency->input (car choice)))
     (('conditional-value val condition)
      (dependency->name val))))