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Avoid tech collision.

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Closes #1484.
This commit is contained in:
Vincent St-Amour 2016-10-09 10:54:53 -05:00
parent e340719e5e
commit 241d87c011
1 changed files with 16 additions and 12 deletions
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28
pkgs/racket-doc/scribblings/reference/stx-props.scrbl
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@ -5,10 +5,11 @@
Every syntax object has an associated @deftech{syntax property} list,
which can be queried or extended with
@racket[syntax-property]. A property is set as @tech{preserved} or not;
a preserved property is maintained for a syntax object in a compiled form that is
marshaled to a byte string or @filepath{.zo} file, and other properties
are discarded when marshaling.
@racket[syntax-property]. A property is set as
@deftech[#:key "stx-prop-preserved"]{preserved} or not; a preserved property is
maintained for a syntax object in a compiled form that is marshaled to a byte
string or @filepath{.zo} file, and other properties are discarded when
marshaling.
In @racket[read-syntax], the reader attaches a preserved @racket['paren-shape]
property to any pair or vector syntax object generated from parsing a
@ -24,7 +25,8 @@ are merged by the syntax expander: each property in the original and
not present in the result is copied to the result, and the values of
properties present in both are combined with @racket[cons] (result
value first, original value second) and the @racket[cons]ed value is
@tech{preserved} if either of the values were preserved.
@tech[#:key "stx-prop-preserved"]{preserved} if either of the values were
preserved.
Before performing the merge, however, the syntax expander
automatically adds a property to the original syntax object using the
@ -39,7 +41,8 @@ list of identifiers. However, a transformer might return
syntax that has already been expanded, in which case an
@racket['origin] list can contain other lists after a merge. The
@racket[syntax-track-origin] procedure implements this tracking.
The @racket['origin] property is added as non-@tech{preserved}.
The @racket['origin] property is added as
non-@tech[#:key "stx-prop-preserved"]{preserved}.
Besides @racket['origin] tracking for general macro expansion,
Racket adds properties to expanded syntax (often using
@ -116,10 +119,10 @@ information on properties and byte codes.
The three- or four-argument form extends @racket[stx] by associating
an arbitrary property value @racket[v] with the key @racket[key]; the
result is a new syntax object with the association (while @racket[stx]
itself is unchanged). The property is added as @tech{preserved} if
@racket[preserved?] is true, in which case @racket[key] must be an
@tech{interned} symbol, and @racket[v] should be a value as described
below that can be saved in marshaled bytecode.
itself is unchanged). The property is added as
@tech[#:key "stx-prop-preserved"]{preserved} if @racket[preserved?] is true, in
which case @racket[key] must be an @tech{interned} symbol, and @racket[v]
should be a value as described below that can be saved in marshaled bytecode.
The two-argument form returns an arbitrary property value associated
to @racket[stx] with the key @racket[key], or @racket[#f] if no value
@ -157,8 +160,9 @@ attempt to marshal the owning syntax object to bytecode form.
@defproc[(syntax-property-preserved? [stx syntax?] [key (and/c symbol? symbol-interned?)])
boolean?]{
Returns @racket[#t] if @racket[stx] has a @tech{preserved} property
value for @racket[key], @racket[#f] otherwise.
Returns @racket[#t] if @racket[stx] has a
@tech[#:key "stx-prop-preserved"]{preserved} property value for @racket[key],
@racket[#f] otherwise.
@history[#:added "6.4.0.14"]}