#
#
# add_file "selectors.g"
#  content [98a7d1fece832b1c074746554692188a80c21a42]
#
============================================================
--- selectors.g	98a7d1fece832b1c074746554692188a80c21a42
+++ selectors.g	98a7d1fece832b1c074746554692188a80c21a42
@@ -0,0 +1,44 @@
+grammar selectors;
+
+//setOperator : ( 'heads' | 'h' | 'erase_ancestors' | 'parent' | 'p' | 'leaves' );
+
+input : difference EOF;
+
+difference : union ( '-' union )*;
+
+union : intersection ( ',' intersection )*;
+
+intersection : selector ( '/' selector )*;
+
+selector :
+  immediate
+| '(' difference ')'
+//| Difference
+//| PrefixOperator
+| function1 '(' difference ')'
+//| Operator2 "(" Number10 "," Selector ")"
+;
+
+immediate :
+  Identifier
+| BranchName
+| AuthorName
+;
+
+function1 :
+  'h' | 'heads'
+| 'lca'
+| 'p' | 'parents'
+;
+
+Identifier : 'i:' ('0'..'9'|'a'..'f'|'A'..'F')+;
+
+BranchName : 'b:' (
+  ('a'..'z'|'0'..'9'|'-'|'_'|'.'|'@')+
+| '"' (~('\r'|'\n'|'\t'|' '|'\''|'"'|'\\')|'\\' .)+ '"'
+);
+
+AuthorName : 'a:' (
+  ('a'..'z'|'0'..'9'|'-'|'_'|'.'|'@')+
+| '"' (~('\r'|'\n'|'\t'|' '|'\''|'"'|'\\')|'\\' .)+ '"'
+);