pre-global-post-section.scrbl (1107B)
1 #lang scribble/manual 2 3 @title{Pre, global and post operations} 4 5 Pre operations happen before the @racket[~!] backtracking cut, so they can 6 affect what combination of alternative clauses the parser will choose. Post 7 operations happen after the @racket[~!] backtracking cut, and can only reject 8 the @racket[~no-order] or @racket[~seq-no-order] as a whole (i.e. different 9 orders will not be attempted after a @racket[~post-fail]. Global operations will 10 always succeed. 11 12 Post operations can access the attributes defined by global and pre operations 13 as well as attributes defined by the alternative clauses. Global operations 14 cannot access the attributes of post operations, and pre operations cannot 15 access the attributes of global and post operations. See 16 @secref["Order_in_which_the_attributes_are_bound_for_post_operations_and_global_operations" 17 #:doc '(lib "extensible-parser-specifications/scribblings/extensible-parser-specifications.scrbl")] 18 for more details. 19 20 @include-section{pre.scrbl} 21 @include-section{global.scrbl} 22 @include-section{post.scrbl} 23 @include-section{pre-global-post-order.scrbl}