24 lines
1.1 KiB
Racket
24 lines
1.1 KiB
Racket
#lang scribble/manual
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@title{Post operations and global operations}
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Pre operations happen before the @racket[~!] backtracking cut, so they can
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affect what combination of alternative clauses the parser will choose. Post
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operations happen after the @racket[~!] backtracking cut, and can only reject
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the @racket[~no-order] or @racket[~seq-no-order] as a whole (i.e. different
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orders will not be attempted after a @racket[~post-fail]. Global operations will
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always succeed.
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Post operations can access the attributes defined by global and pre operations
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as well as attributes defined by the alternative clauses. Global operations
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cannot access the attributes of post operations, and pre operations cannot
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access the attributes of global and post operations. See
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@secref["Order_in_which_the_attributes_are_bound_for_post_operations_and_global_operations"
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#:doc '(lib "extensible-parser-specifications/scribblings/extensible-parser-specifications.scrbl")]
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for more details.
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@include-section{pre.scrbl}
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@include-section{global.scrbl}
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@include-section{post.scrbl}
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@include-section{pre-global-post-order.scrbl}
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