Racket: add steps0-A. Self-hosting.

- Some additioanl tests.
- Split step9 tests into optional but self-hosting requirements
  (metadata on functions) and other optional (conj, metadata on
  collections).

1 files changed, 44 insertions, 0 deletions

diff --git a/racket/printer.rkt b/racket/printer.rkt
new file mode 100644
index 0000000..07a8bb8
--- /dev/null
+++ b/racket/printer.rkt
@@ -0,0 +1,44 @@
+#lang racket
+
+(provide pr_str pr_lst)
+
+(require "types.rkt")
+
+(define (pr_str obj print_readably)
+  (let ([_r print_readably])
+    (cond
+      [(list? obj)
+       (string-join (map (lambda (o) (pr_str o _r)) obj)
+                    " " #:before-first "(" #:after-last ")")]
+      [(vector? obj)
+       (string-join (map (lambda (o) (pr_str o _r)) (vector->list obj))
+                    " " #:before-first "[" #:after-last "]")]
+      [(hash? obj)
+       (string-join (dict-map obj (lambda (k v)
+                                    (format "~a ~a"
+                                            (pr_str k _r)
+                                            (pr_str v _r))))
+                    " " #:before-first "{" #:after-last "}")]
+      [(string? obj)
+       (if (regexp-match #px"^\u029e" obj)
+         (format ":~a" (substring obj 1))
+         (if _r
+           (format "\"~a\""
+             (string-replace
+               (string-replace
+                 (string-replace obj "\\" "\\\\")
+                 "\"" "\\\"")
+                "\n" "\\n"))
+           obj))]
+      [(number? obj) (number->string obj)]
+      [(symbol? obj) (symbol->string obj)]
+      [(atom? obj) (format "(atom ~a)" (atom-val obj))]
+      [(_nil? obj) "nil"]
+      [(eq? #t obj) "true"]
+      [(eq? #f obj) "false"]
+      [else (format "~a" obj)])))
+
+(define (pr_lst lst print_readably sep)
+  (string-join
+    (map (lambda (s) (pr_str s print_readably)) lst)
+    sep))