d7a87c79e0
Changed backtracking algorithm, runtime representations
- syntax classes, ~describe no longer implicitly commit
- ~describe no longer delimits effect of cut
Added keyword & optional args for stxclasses
Added ~do and #:do, ~post, ~commit and #:commit,
~delimit-cut and #:no-delimit-cut
Added syntax/parse/debug, syntax/parse/experimental/*
- expr/c for contracting macro sub-expressions
moved from syntax/parse to syntax/parse/experimental/contract
- syntax class reflection (~reflect, ~splicing-reflect)
- eh-alternative-sets (~eh-var)
- provide-syntax-class/contract
(only for params, not attrs so far)
Changed ~fail to not include POST progress (#:fail still does)
old (~fail _) is now (~post (~fail _))
Made msg argument of ~fail optional
Removed generic "repetition constraint violated" msg
Removed atom-in-list stxclass
Removed unnecessary datum->syntax on cdr of pair pattern
massive improvements to long-list microbenchmarks
Optimization: integrable syntax classes (id, expr, keyword)
need better measurements
Optimization: ad hoc elimination of head/tail choice point
for (EH ... . ()) patterns
Added unstable/wrapc (proc version of expr/c)
57 lines
2.0 KiB
Racket
57 lines
2.0 KiB
Racket
#lang scribble/doc
|
|
@(require scribble/manual
|
|
scribble/struct
|
|
scribble/decode
|
|
scribble/eval
|
|
"parse-common.rkt")
|
|
|
|
@title{Debugging and inspection tools}
|
|
|
|
@defmodule[syntax/parse/debug]
|
|
|
|
The following special forms are for debugging syntax classes.
|
|
|
|
@defform[(syntax-class-attributes syntax-class-id)]{
|
|
|
|
Returns a list of the syntax class's attributes. Each attribute entry
|
|
consists of the attribute's name and ellipsis depth.
|
|
}
|
|
|
|
@deftogether[[
|
|
@defform[(syntax-class-arity syntax-class-id)]
|
|
@defform[(syntax-class-keywords syntax-class-id)]]]{
|
|
|
|
Returns the syntax class's arity and keywords, respectively. Compare
|
|
with @scheme[procedure-arity] and @scheme[procedure-keywords].
|
|
}
|
|
|
|
@defform[(syntax-class-parse syntax-class-id stx-expr arg ...)
|
|
#:contracts ([stx-expr syntax?])]{
|
|
|
|
Runs the parser for the syntax class (parameterized by the
|
|
@scheme[arg-expr]s) on the syntax object produced by
|
|
@scheme[stx-expr]. On success, the result is a list of vectors
|
|
representing the attribute bindings of the syntax class. Each vector
|
|
contains the attribute name, depth, and associated value. On failure,
|
|
the result is some internal representation of the failure.
|
|
}
|
|
|
|
@defform[(debug-parse stx-expr S-pattern ...+)
|
|
#:contracts ([stx-expr syntax?])]{
|
|
|
|
Tries to match @scheme[stx-expr] against the @scheme[S-pattern]s. If
|
|
matching succeeds, the the symbol @scheme['success] is
|
|
returned. Otherwise, an S-expression describing the failure is returned.
|
|
|
|
The failure S-expression shows both the raw set of failures (unsorted)
|
|
and the failures with maximal progress. The maximal failures are
|
|
divided into equivalence classes based on their progress (progress is
|
|
a partial order); that is, failures within an equivalence class have
|
|
the same progress and, in principle, pinpoint the same term as the
|
|
problematic term. Multiple equivalence classes only arise from
|
|
@scheme[~parse] patterns (or equivalently, @scheme[#:with] clauses)
|
|
that match computed terms or @scheme[~fail] (@scheme[#:fail-when],
|
|
etc) clauses that allow a computed term to be pinpointed.
|
|
|
|
}
|