diff options
| -rw-r--r-- | guix/records.scm | 65 | ||||
| -rw-r--r-- | tests/records.scm | 38 |
2 files changed, 89 insertions, 14 deletions
diff --git a/guix/records.scm b/guix/records.scm index 3d54a51956..ed94c83dac 100644 --- a/guix/records.scm +++ b/guix/records.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org> +;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Ludovic Courtès <ludo@gnu.org> ;;; Copyright © 2018 Mark H Weaver <mhw@netris.org> ;;; ;;; This file is part of GNU Guix. @@ -120,7 +120,8 @@ context of the definition of a thunked field." "Make the syntactic constructor NAME for TYPE, that calls CTOR, and expects all of EXPECTED fields to be initialized. DEFAULTS is the list of FIELD/DEFAULT-VALUE tuples, THUNKED is the list of identifiers of thunked -fields, and DELAYED is the list of identifiers of delayed fields. +fields, DELAYED is the list of identifiers of delayed fields, and SANITIZERS +is the list of FIELD/SANITIZER tuples. ABI-COOKIE is the cookie (an integer) against which to check the run-time ABI of TYPE matches the expansion-time ABI." @@ -130,6 +131,7 @@ of TYPE matches the expansion-time ABI." #:this-identifier this-identifier #:delayed delayed #:innate innate + #:sanitizers sanitizers #:defaults defaults) (define-syntax name (lambda (s) @@ -169,19 +171,30 @@ of TYPE matches the expansion-time ABI." (define (innate-field? f) (memq (syntax->datum f) 'innate)) + (define field-sanitizer + (let ((lst (map (match-lambda + ((f p) + (list (syntax->datum f) p))) + #'sanitizers))) + (lambda (f) + (or (and=> (assoc-ref lst (syntax->datum f)) car) + #'(lambda (x) x))))) + (define (wrap-field-value f value) - (cond ((thunked-field? f) - #`(lambda (x) - (syntax-parameterize ((#,this-identifier - (lambda (s) - (syntax-case s () - (id - (identifier? #'id) - #'x))))) - #,value))) - ((delayed-field? f) - #`(delay #,value)) - (else value))) + (let* ((sanitizer (field-sanitizer f)) + (value #`(#,sanitizer #,value))) + (cond ((thunked-field? f) + #`(lambda (x) + (syntax-parameterize ((#,this-identifier + (lambda (s) + (syntax-case s () + (id + (identifier? #'id) + #'x))))) + #,value))) + ((delayed-field? f) + #`(delay #,value)) + (else value)))) (define default-values ;; List of symbol/value tuples. @@ -291,6 +304,19 @@ can access the record it belongs to via the 'this-thing' identifier. A field can also be marked as \"delayed\" instead of \"thunked\", in which case its value is effectively wrapped in a (delay …) form. +A field can also have an associated \"sanitizer\", which is a procedure that +takes a user-supplied field value and returns a \"sanitized\" value for the +field: + + (define-record-type* <thing> thing make-thing + thing? + this-thing + (name thing-name + (sanitize (lambda (value) + (cond ((string? value) value) + ((symbol? value) (symbol->string value)) + (else (throw 'bad! value))))))) + It is possible to copy an object 'x' created with 'thing' like this: (thing (inherit x) (name \"bar\")) @@ -307,6 +333,14 @@ inherited." (field-default-value #'(field properties ...))) (_ #f))) + (define (field-sanitizer s) + (syntax-case s (sanitize) + ((field (sanitize proc) _ ...) + (list #'field #'proc)) + ((field _ properties ...) + (field-sanitizer #'(field properties ...))) + (_ #f))) + (define-field-property-predicate delayed-field? delayed) (define-field-property-predicate thunked-field? thunked) (define-field-property-predicate innate-field? innate) @@ -376,6 +410,8 @@ inherited." (innate (filter-map innate-field? field-spec)) (defaults (filter-map field-default-value #'((field properties ...) ...))) + (sanitizers (filter-map field-sanitizer + #'((field properties ...) ...))) (cookie (compute-abi-cookie field-spec))) (with-syntax (((field-spec* ...) (map field-spec->srfi-9 field-spec)) @@ -421,6 +457,7 @@ of a record instantiation" #:this-identifier #'this-identifier #:delayed #,delayed #:innate #,innate + #:sanitizers #,sanitizers #:defaults #,defaults))))) ((_ type syntactic-ctor ctor pred (field get properties ...) ...) diff --git a/tests/records.scm b/tests/records.scm index 706bb3dbfd..d014e7a995 100644 --- a/tests/records.scm +++ b/tests/records.scm @@ -283,6 +283,44 @@ (equal? (foo-bar y) 1)) ;promise was already forced (eq? (foo-baz y) 'b))))) +(test-assert "define-record-type* & sanitize" + (begin + (define-record-type* <foo> foo make-foo + foo? + (bar foo-bar + (default "bar") + (sanitize (lambda (x) (string-append x "!"))))) + + (let* ((p (foo)) + (q (foo (inherit p))) + (r (foo (inherit p) (bar "baz"))) + (s (foo (bar "baz")))) + (and (string=? (foo-bar p) "bar!") + (equal? q p) + (string=? (foo-bar r) "baz!") + (equal? s r))))) + +(test-assert "define-record-type* & sanitize & thunked" + (let ((sanitized 0)) + (define-record-type* <foo> foo make-foo + foo? + (bar foo-bar + (default "bar") + (sanitize (lambda (x) + (set! sanitized (+ 1 sanitized)) + (string-append x "!"))))) + + (let ((p (foo))) + (and (string=? (foo-bar p) "bar!") + (string=? (foo-bar p) "bar!") ;twice + (= sanitized 1) ;sanitizer was called at init time only + (let ((q (foo (bar "baz")))) + (and (string=? (foo-bar q) "baz!") + (string=? (foo-bar q) "baz!") ;twice + (= sanitized 2) + (let ((r (foo (inherit q)))) + (and (string=? (foo-bar r) "baz!") + (= sanitized 2))))))))) ;no re-sanitization (test-assert "define-record-type* & wrong field specifier" (let ((exp '(begin (define-record-type* <foo> foo make-foo |