sunterlib/s48/krims -- Odds and Ends structure SRFI-1+ -- SRFI-1 + REST The structure SRFI-1+ extends the list lib with REST := CDR. [ I dearly like (FIRST . REST) lists and (CAR . CDR) trees. ] * structure SRFI-9+ -- SRFI-9 + DEFINE-RECORD-DISCLOSER The structure SRFI-9+ extends SRFI-9 by the convenient record disclosing facility from DEFINE-RECORD-TYPES: (define-record-type rt predicate ...) SYNTAX just as SRFI-9. (define-record-discloser rt d) --> unspecified PROCEDURE just as DEFINE-RECORD-TYPES: Install the procedure D : rt -> list as discloser for records of type RT where RT has been defined with DEFINE-RECORD-TYPE (from above) and D maps its input record to a printable list starting with a symbol. * structure KRIMS -- Odds and Ends The structure KRIMS gathers miscellaneous tiny utilities mainly for use of other sunterlib projects. (assert exp x0 ...) SYNTAX Signal an error if EXP is false, reporting both the failed assertion EXP (literally) and the values of X0 ... Don't evaluate X0 ... if EXP holds true. * (receive/name loop formals exp form0 ...) SYNTAX RECEIVE/NAME is a multi-values analogue of named LET (but much less useful) that helps when chaining n-valued n-ary functions, for instance. Synopsis: Bind LOOP to a macro wrapped around the procedure LUP with parameter list FORMALS and body FORM0 ... so that * (LOOP multi-valued-expression) calls LUP with the values of multi-valued-expression , and * (LOOP exp0 ...) becomes (LUP exp0 ...) Syntax: (receive/name ) with non-terminals from R5RS. Semantics: (A special case is good enough.) Assuming the LOOP tag isn't shadowed in the context `...' (receive/name loop (x y) exp0 ... (loop exp1) ...) is eqv to (receive (x y) exp0 (let lup ((x x) (y y)) ... (receive (x y) exp1 (lup x y)) ...)) and (receive/name loop (x y) exp0 ... (loop exp1 exp1) ...) is eqv to (receive (x y) exp0 (let lup ((x x) (y y)) ... (lup exp1 exp2) ...)) Example: (define (shove n xs) (values (- n 1) (cons n xs))) (receive/name loop (n xs) (values 7 '()) (if (= n 0) (display xs) (loop (shove n xs)))) ==> (1 2 3 4 5 6 7) * (gen-dispatch ((predicate action) ...) e0 e1 ... en) SYNTAX Dispatch action on type of first argument E0: feed E0 ... EN to the first action such that the PREDICATE holds for E0. Signal an error if nothing goes. Example: (gen-dispatch ((string? string-ref) (vector? vector-ref) (list? list-ref)) '#(a zopp 36) 2) ==> 36 [ Yes, this macro doesn't help much. ] oOo