X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=src%2Fscheme-library.scm;h=2c6146eb57a80948261ef3a552e14188416c1f58;hb=5eea24f47ad60b69af59a76c7285ec232c29009c;hp=fb76f3ae009ae1e874c8dfeda598b0ff1e93b1f7;hpb=0dadd5f58d2c204c7f621ccd3c42f75a3fd790a8;p=scheme.forth.jl.git diff --git a/src/scheme-library.scm b/src/scheme-library.scm index fb76f3a..2c6146e 100644 --- a/src/scheme-library.scm +++ b/src/scheme-library.scm @@ -12,8 +12,14 @@ (define (cadr l) (car (cdr l))) (define (cdar l) (cdr (car l))) (define (cddr l) (cdr (cdr l))) +(define (caaar l) (car (car (car l)))) +(define (caadr l) (car (car (cdr l)))) (define (cadar l) (car (cdr (car l)))) (define (caddr l) (car (cdr (cdr l)))) +(define (cdaar l) (cdr (car (car l)))) +(define (cdadr l) (cdr (car (cdr l)))) +(define (cddar l) (cdr (cdr (car l)))) +(define (cdddr l) (cdr (cdr (cdr l)))) (define (cadddr l) (car (cdr (cdr (cdr l))))) ;; FUNCTIONAL PROGRAMMING @@ -203,6 +209,10 @@ (define (integer? x) (= x (round x))) (define (exact? x) (fixnum? x)) (define (inexact? x) (flonum? x)) +(define (number? x) + (if (fixnum? x) #t + (if (flonum? x) #t + (if (ratnum? x) #t #f)))) ;; LISTS @@ -239,19 +249,9 @@ ; let -(define (let-vars args) - (if (null? args) - '() - (cons (caar args) (let-vars (cdr args))))) - -(define (let-inits args) - (if (null? args) - '() - (cons (cadar args) (let-inits (cdr args))))) - (define-macro (let args . body) - `((lambda ,(let-vars args) - ,@body) ,@(let-inits args))) + `((lambda ,(map (lambda (x) (car x)) args) + ,@body) ,@(map (lambda (x) (cadr x)) args))) ; while @@ -265,61 +265,66 @@ ; cond -(define (cond-predicate clause) (car clause)) -(define (cond-actions clause) (cdr clause)) -(define (cond-else-clause? clause) - (eq? (cond-predicate clause) 'else)) - -(define (expand-clauses clauses) - (display "Expanding cond clauses...") - (if (null? clauses) - (none) - (let ((first (car clauses)) - (rest (cdr clauses))) - (if (cond-else-clause? first) - (if (null? rest) - `(begin ,@(cond-actions first)) - (error "else clause isn't last in cond expression.")) - `(if ,(cond-predicate first) - (begin ,@(cond-actions first)) - ,(expand-clauses rest)))))) - -(define-macro (cond . clauses) - (if (null? clauses) - (error "cond requires at least one clause.") - (expand-clauses clauses))) +((lambda () + (define (cond-predicate clause) (car clause)) + (define (cond-actions clause) (cdr clause)) + (define (cond-else-clause? clause) + (eq? (cond-predicate clause) 'else)) + + (define (expand-clauses clauses) + (if (null? clauses) + (none) + (let ((first (car clauses)) + (rest (cdr clauses))) + (if (cond-else-clause? first) + (if (null? rest) + `(begin ,@(cond-actions first)) + (error "else clause isn't last in cond expression.")) + `(if ,(cond-predicate first) + (begin ,@(cond-actions first)) + ,(expand-clauses rest)))))) + + (define-macro (cond . clauses) + (if (null? clauses) + (error "cond requires at least one clause.") + (expand-clauses clauses))) + )) ; and -(define (expand-and-expressions expressions) - (let ((first (car expressions)) - (rest (cdr expressions))) - (if (null? rest) - first - `(if ,first - ,(expand-and-expressions rest) - #f)))) - -(define-macro (and . expressions) - (if (null? expressions) - #t - (expand-and-expressions expressions))) +((lambda () + (define (expand-and-expressions expressions) + (let ((first (car expressions)) + (rest (cdr expressions))) + (if (null? rest) + first + `(if ,first + ,(expand-and-expressions rest) + #f)))) + + (define-macro (and . expressions) + (if (null? expressions) + #t + (expand-and-expressions expressions))) + )) ; or -(define (expand-or-expressions expressions) - (if (null? expressions) - #f - (let ((first (car expressions)) - (rest (cdr expressions)) - (val (gensym))) - `(let ((,val ,first)) - (if ,val - ,val - ,(expand-or-expressions rest)))))) - -(define-macro (or . expressions) - (expand-or-expressions expressions)) +((lambda () + (define (expand-or-expressions expressions) + (if (null? expressions) + #f + (let ((first (car expressions)) + (rest (cdr expressions)) + (val (gensym))) + `(let ((,val ,first)) + (if ,val + ,val + ,(expand-or-expressions rest)))))) + + (define-macro (or . expressions) + (expand-or-expressions expressions)) + )) ;; TESTING