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| author | Arun Isaac | 2021-07-20 15:53:43 +0530 |
|---|---|---|
| committer | Arun Isaac | 2021-07-20 15:58:32 +0530 |
| commit | be338a13488a219bed1ae96d5c264d09c4c35efd (patch) | |
| tree | cce472d4af64a3f0e6abc511275a73420e0a84d8 /ccwl | |
| parent | 2eccdc9fbc8b1ed0666ef82d0e1e280b85945b3c (diff) | |
| download | ccwl-be338a13488a219bed1ae96d5c264d09c4c35efd.tar.gz ccwl-be338a13488a219bed1ae96d5c264d09c4c35efd.tar.lz ccwl-be338a13488a219bed1ae96d5c264d09c4c35efd.zip | |
ccwl: Support default values for arguments in lambda**.
* ccwl/utils.scm (lambda**): Support default values for arguments,
both unary and n-ary.
* tests/utils.scm ("lambda** with default values"): New test.
Diffstat (limited to 'ccwl')
| -rw-r--r-- | ccwl/utils.scm | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/ccwl/utils.scm b/ccwl/utils.scm index b4e167e..14b1c0a 100644 --- a/ccwl/utils.scm +++ b/ccwl/utils.scm @@ -135,7 +135,15 @@ for example, be invoked as: (list a b foo bar)) 1 2 #:foo 123 #:bar 1 2 3) -=> (1 2 123 (1 2 3))" +=> (1 2 123 (1 2 3)) + +lambda** also supports default values for both unary and n-ary keyword +arguments. For example, + +((lambda** (foo aal #:key vale (pal 9) #:key* naal (irandu 7) (sol 3 2 1)) + (list foo aal vale pal naal irandu sol)) + 1 2 #:vale 123 #:naal 321 456) +=> (1 2 123 9 (321 456) (7) (3 2 1))" (syntax-case x () ((_ (args-spec ...) body ...) #`(lambda args @@ -147,12 +155,23 @@ for example, be invoked as: (nary-arguments (or (plist-ref grouped-rest #:key*) (list)))) #`(apply (lambda* #,(append positionals - (cons #:key (append unary-arguments nary-arguments))) + (cons #:key unary-arguments) + (map (lambda (x) + (syntax-case x () + ((arg defaults ...) + #'(arg (list defaults ...))) + (arg #'arg))) + nary-arguments)) body ...) (let ((positionals rest (break keyword? args))) (append positionals (group-keyword-arguments - rest (list #,@(map (compose symbol->keyword syntax->datum) + rest (list #,@(map (lambda (x) + (symbol->keyword + (syntax->datum + (syntax-case x () + ((arg default) #'arg) + (arg #'arg))))) unary-arguments)))))))))))) (define-syntax-rule (syntax-lambda** formal-args body ...) |