diff options
| -rw-r--r-- | stdlib/op.tl | 12 | ||||
| -rw-r--r-- | tests/012/op.tl | 44 | ||||
| -rw-r--r-- | txr.1 | 84 |
3 files changed, 114 insertions, 26 deletions
diff --git a/stdlib/op.tl b/stdlib/op.tl index d1c1f3e7..a3a0135e 100644 --- a/stdlib/op.tl +++ b/stdlib/op.tl @@ -107,17 +107,20 @@ (defmacro op-ignerr (x) ^(sys:catch (error) ,x () (error (. args) (ignore args))))) +(defparml compat-225 (and (plusp sys:compat) (<= sys:compat 225))) + +(defparml compat-298 (and (plusp sys:compat) (<= sys:compat 298))) + (defun sys:op-expand (f e args) (unless args ['compile-error f "arguments required"]) - (let* ((compat (and (plusp sys:compat) (<= sys:compat 225))) - (ctx (make-struct 'sys:op-ctx ^(form ,f))) + (let* ((ctx (make-struct 'sys:op-ctx ^(form ,f))) (sys:*op-ctx* ctx) (sym (car f)) (do-gen (if (eq sym 'do) (gensym))) (syntax-0 (if (eq sym 'do) args ^[,*args])) - (syntax-1 (if (or (null syntax-0) (neq sym 'do) compat) - ;; Not do, or empty do syntax, or compat mode. + (syntax-1 (if (or (null syntax-0) (neq sym 'do) compat-225) + ;; Not do, or empty do syntax, or compat 225 mode. (sys:op-alpha-rename e syntax-0 nil) ;; Try to expand args as-is, catching errors. (let ((syn (op-ignerr (sys:op-alpha-rename e @@ -161,6 +164,7 @@ (lambda-interior (let ((fargs (tree-case syntax-2 ((t t . fa) fa)))) (cond + ((and metas (not compat-298)) syntax-2) ((and (eq sym 'lop) fargs) (let ((fargs-l1 (mapcar (lambda (farg) ^(sys:l1-val ,farg)) diff --git a/tests/012/op.tl b/tests/012/op.tl index 47f1f80d..34f7ef39 100644 --- a/tests/012/op.tl +++ b/tests/012/op.tl @@ -41,6 +41,18 @@ (fi (do if @1 @3 @rest @2)) (3 t)) (mtest + (fi (lop)) :error + (fi (lop list)) (0 t) + (fi (lop list @1)) (1 t) + (fi (lop list @2)) (2 t) + (fi (lop list @42)) (42 t) + (fi (lop list @rest)) (0 t) + (fi (lop list @1 @rest)) (1 t) + (fi (lop list @2 @rest)) (2 t) + (fi (lop list @42 @rest)) (42 t) + (fi (lop list @1 @3 @rest @2)) (3 t)) + +(mtest [(do quote x) 3] :error [(do quote @1) 3] :error (do pop a) :error) @@ -78,12 +90,22 @@ (mtest [[(do op list)] 2] :error [[(do op list) 2]] (2) + [[(do op list 3) 2]] (3 2) [[(do op list @@1) 1] 2] (1 2) [[(do op list @1)] 2] :error [[(do op list @1) 1] 2] (2 1) [[(do op list @@1 @1) 1] 2] (1 2)) (mtest + [[(do lop list)] 2] :error + [[(do lop list) 2]] (2) + [[(do lop list 3) 2]] (3 2) + [[(do lop list @@1) 1] 2] (2 1) + [[(do lop list @1)] 2] :error + [[(do lop list @1) 1] 2] (2 1) + [[(do lop list @@1 @1) 1] 2] (1 2)) + +(mtest [[[[(do do do op list @1) 1] 2] 3] 4] (4 1 2 3) [[[[(do do do op list @@1) 1] 2] 3] 4] (3 1 2 4) [[[[(do do do op list @@@1) 1] 2] 3] 4] (2 1 3 4) @@ -125,3 +147,25 @@ (tap inc y @1)) y)) (13 23)) + +(mtest + [(op list) 1 2 3] (1 2 3) + [(op list 0) 1 2 3] (0 1 2 3) + [(op list 0 4) 1 2 3] (0 4 1 2 3) + [(op list @1) 1 2 3] (1) + [(op list @2) 1 2 3] (2) + [(op list @3) 1 2 3] (3) + [(op list 0 @3) 1 2 3] (0 3) + [(op list 0 4 @3) 1 2 3] (0 4 3) + [(op list . @rest) 1 2 3] (1 2 3)) + +(mtest + [(lop list) 1 2 3] (1 2 3) + [(lop list 0) 1 2 3] (1 2 3 0) + [(lop list 0 4) 1 2 3] (1 2 3 0 4) + [(lop list @1) 1 2 3] (1) + [(lop list @2) 1 2 3] (2) + [(lop list @3) 1 2 3] (3) + [(lop list 0 @3) 1 2 3] (0 3) + [(lop list 0 4 @3) 1 2 3] (0 4 3) + [(lop list . @rest) 1 2 3] (1 2 3)) @@ -60417,7 +60417,9 @@ in which they are passed to .desc The .code lop -macro is variant of +macro, (\(dqleft-inserting +.codn op \(dq), +is variant of .code op with special semantics. @@ -60434,13 +60436,32 @@ is given then is equivalent to .codn op . -If two or more -.meta form -arguments are present, then +Likewise, if any meta-number arguments or +.code @rest +are represent, .code lop -generates a variadic function which inserts all of its trailing -arguments between the first and second -.metn form s. +is equivalent to +.codn op . + +The difference between +.code op +and +.code lop +lies in the implicit insertion of the +.code @rest +arguments. + +In cases when +.code op +implicitly adds the resulting function's arguments to the right of the bound +arguments given by the +.metn form -s, +the +.code lop +macro instead inserts the function's arguments into the left position, +between the first and second +.meta form +arguments. That is to say, trailing arguments coming into the anonymous function become the left arguments of the function or function-like object @@ -60448,22 +60469,16 @@ denoted by the first .meta form and the remaining .metn form s -give additional arguments. Hence the name -.codn lop , -which stands for \(dqleft-inserting -.codn op \(dq. - -This left insertion of the trailing arguments takes place regardless of whether -.code @rest -occurs in any -.metn form . +give additional arguments. -The -.meta form -syntax determines the number of required arguments of the -generated function, according to the highest-valued meta-number. The trailing -arguments which are inserted into the left position are any arguments in excess -of the required arguments. +Thus, whereas +.code "(op - 1 2 3)" +denotes a function similar to +.codn "(lambda (. args) [- 1 2 3 . args])" , +the expression +.code "(lop - 1 2 3)" +denotes +.codn "(lambda (. args) [apply - (append args [list 1 2 3])])" . The .code lop @@ -60482,6 +60497,25 @@ are replaced with hygienic, unique symbols. (lop f x y) <--> (lambda (. rest) [apply f (append rest [list x y])]) + ;; same as (op f x @3 y) + (lop f x @3 y) <--> (lambda (arg1 arg2 arg3 . rest) + [f x arg3 y]) +.brev + +Compatibility Note: until \*(TX 298, the implicit left insertion of the +trailing arguments takes place regardless of whether +.code @rest +or any meta-number arguments occur in the form, meaning that +.code lop +forms which have those arguments are not equivalent to +.codn op . +This is affected by the compatibility option, and hence mentioned in the +COMPATIBILITY section. Under the old behavior, the previously given +equivalence above is instead: + +.verb + ;; the trailing arguments after the fixed ones + ;; are inserted in the function's left position (lop f x @3 y) <--> (lambda (arg1 arg2 arg3 . rest) [apply f (append rest @@ -95122,6 +95156,12 @@ of these version values, the described behaviors are provided if is given an argument which is equal or lower. For instance .code "-C 103" selects the behaviors described below for version 105, but not those for 102. +.IP 298 +Until \*(TX 298, the +.code lop +macro has a certain behavior which has changed. That behavior is restored +with compatibility values of 298 or lower. More details are given in +the description of that macro. .IP 294 Until \*(TX 294, the .code pprint |