c4 23

Author: seckcoder

src/eval/c4_23.scm

@@ -0,0 +1,5 @@
+; I've implemented one analyze-sequence in eval1.scm,
+; the text has a version of analyze-sequence(analyze-sequence-text in eval1.scm)
+; and analyze-sequence-alyssa has a version of analyze-sequence(analyze-sequence-alyssa).
+; Of those, analyze-sequence-text and my version are better. Since they try to expand all the sequence
+; during the analysis stage(try to add a print func in loop).

src/eval/eval1.scm

@@ -69,17 +69,46 @@
     (lambda (env) (make-procedure params body-proc env))))
 
 (define (analyze-sequence exp)
+  (define (combine proc1 proc2)
+    (lambda (env)
+      (proc1 env)
+      (proc2 env)))
   (define (combine-seq-proc seq-proc)
+    ; (println "combine-seq-proc")
     (if (null? (cdr seq-proc))
       (car seq-proc)
-      (lambda (env)
-        ((car seq-proc) env)
-        ((combine-seq-proc (cdr seq-proc)) env))))
+      (combine (car seq-proc)
+               (combine-seq-proc (cdr seq-proc)))))
   (let ((seq-proc (map analyze exp)))
     (if (null? seq-proc)
       (error 'analyze-sequence "no expression in code block")
       (combine-seq-proc seq-proc))))
 
+(define (analyze-sequence-text exps)
+  (define (sequentially proc1 proc2)
+    (lambda (env) (proc1 env) (proc2 env)))
+  (define (loop first-proc rest-procs)
+    ; (println "loop")
+    (if (null? rest-procs)
+        first-proc
+        (loop (sequentially first-proc (car rest-procs))
+              (cdr rest-procs))))
+  (let ((procs (map analyze exps)))
+    (if (null? procs)
+        (error "Empty sequence -- ANALYZE"))
+    (loop (car procs) (cdr procs))))
+
+(define (analyze-sequence-alyssa exps)
+  (define (execute-sequence procs env)
+    (cond ((null? (cdr procs))
+           ((car procs) env))
+          (else ((car procs) env)
+                (execute-sequence (cdr procs) env))))
+  (let ((procs (map analyze exps)))
+    (if (null? procs)
+        (error "Empty sequence -- ANALYZE"))
+    (lambda (env) (execute-sequence procs env))))
+
 (define (analyze-application exp)
   (let ((fproc (analyze (operator exp)))
         (aprocs (map analyze (operand exp))))
@@ -125,3 +154,11 @@
                 (set! a (* a b))
                 (+ a b))
              global-env))
+
+(define seq1 '((set! a b)
+               (cons a b)
+               (cons a b)
+               (cons a b)
+               (cons a b)))
+
+(define seq2 '((cons a b)))