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edits to make- APIs for projections

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mostly making the name of the #:first-order argument be first-order
This commit is contained in:
Robby Findler 2020-07-04 16:23:20 -05:00
parent d62526d290
commit ddacbfa174
1 changed files with 19 additions and 17 deletions
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36
pkgs/racket-doc/scribblings/reference/contracts.scrbl
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@ -2289,7 +2289,7 @@ accepted by the third argument to @racket[datum->syntax].
@deftogether[(
@defproc[(make-contract
[#:name name any/c 'anonymous-contract]
[#:first-order test (-> any/c any/c) (λ (x) #t)]
[#:first-order first-order (-> any/c any/c) (λ (x) #t)]
[#:late-neg-projection
late-neg-proj
(or/c #f (-> blame? (-> any/c any/c any/c)))
@ -2305,7 +2305,7 @@ accepted by the third argument to @racket[datum->syntax].
[#:projection proj (-> blame? (-> any/c any/c))
(λ (b)
(λ (x)
(if (test x)
(if (first-order x)
x
(raise-blame-error
b x
@ -2321,7 +2321,7 @@ accepted by the third argument to @racket[datum->syntax].
contract?]
@defproc[(make-chaperone-contract
[#:name name any/c 'anonymous-chaperone-contract]
[#:first-order test (-> any/c any/c) (λ (x) #t)]
[#:first-order first-order (-> any/c any/c) (λ (x) #t)]
[#:late-neg-projection
late-neg-proj
(or/c #f (-> blame? (-> any/c any/c any/c)))
@ -2337,7 +2337,7 @@ accepted by the third argument to @racket[datum->syntax].
[#:projection proj (-> blame? (-> any/c any/c))
(λ (b)
(λ (x)
(if (test x)
(if (first-order x)
x
(raise-blame-error
b x
@ -2353,7 +2353,7 @@ accepted by the third argument to @racket[datum->syntax].
chaperone-contract?]
@defproc[(make-flat-contract
[#:name name any/c 'anonymous-flat-contract]
[#:first-order test (-> any/c any/c) (λ (x) #t)]
[#:first-order first-order (-> any/c any/c) (λ (x) #t)]
[#:late-neg-projection
late-neg-proj
(or/c #f (-> blame? (-> any/c any/c any/c)))
@ -2369,7 +2369,7 @@ accepted by the third argument to @racket[datum->syntax].
[#:projection proj (-> blame? (-> any/c any/c))
(λ (b)
(λ (x)
(if (test x)
(if (first-order x)
x
(raise-blame-error
b x
@ -2396,12 +2396,13 @@ higher-order contracts is @racketresult[anonymous-contract], for
@tech{chaperone contracts} is @racketresult[anonymous-chaperone-contract], and for
@tech{flat contracts} is @racketresult[anonymous-flat-contract].
The first-order predicate @racket[test] is used to determine which values
The first-order predicate @racket[first-order] is used to determine which values
the contract applies to. This test is used
by @racket[contract-first-order-passes?], and indirectly by @racket[or/c]
and @racket[from-or/c] to determine which higher-order contract to wrap a
and @racket[first-or/c] to determine which higher-order contract to wrap a
value with when there are multiple higher-order contracts to choose from.
The default test accepts any value. The predicate should be influenced by
The default value accepts any value, but it must match the behavior of the
projection argument (see below for how). The predicate should be influenced by
the value of @racket[(contract-first-order-okay-to-give-up?)] (see it's documentation
for more explanation).
@ -2435,21 +2436,22 @@ The @racket[val-first-proj] is like @racket[late-neg-proj], except with
an extra layer of currying.
At least one of the @racket[late-neg-proj], @racket[proj],
@racket[val-first-proj], or @racket[test] must be non-@racket[#f].
@racket[val-first-proj], or @racket[first-order] must be non-@racket[#f].
The projection arguments (@racket[late-neg-proj], @racket[proj], and
@racket[val-first-proj]) must be in sync with the @racket[test] argument.
In particular, if the test argument returns @racket[#f] for some value,
@racket[val-first-proj]) must be in sync with the @racket[first-order] argument.
In particular, if the @racket[first-order] argument returns @racket[#f] for some value,
then the projections must raise a blame error for that value and if the
test argument returns @racket[#t] for some value, then the projection must
@racket[first-order] argument returns @racket[#t] for some value, then the projection must
not signal any blame for this value, unless there are higher-order interactions
later. In other words, for @tech{flat contracts}, the @racket[test] and
@racket[projection] arguments must check the same predicate (which is
why thee default projection uses the @racket[test] argument directly).
later. In other words, for @tech{flat contracts}, the @racket[first-order] and
@racket[projection] arguments must check the same predicate. For convenience, the
the default projection uses the @racket[first-order] argument, signalling an error
when it returns @racket[#f] and never signalling one otherwise.
Projections for @tech{chaperone contracts} must produce a value that passes
@racket[chaperone-of?] when compared with the original, uncontracted value.
Projections for @tech{flat contracts} must fail precisely when the first-order test
Projections for @tech{flat contracts} must fail precisely when @racket[first-order]
does, and must produce the input value unchanged otherwise. Applying a
@tech{flat contract} may result in either an application of the predicate, or the
projection, or both; therefore, the two must be consistent. The existence of a