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petitparser/lib/src/lisp/standard.dart

-part of lisp;
-
-/**
- * The standard library.
- */
-class Standard {
-
-  /** Imports the standard library into the [environment]. */
-  static Environment import(Environment environment) {
-    evalString(lispParser, environment, _standardLibrary);
-    return environment;
-  }
-
-  /** A simple standard library, should be moved to external file. */
-  static String _standardLibrary = """
-; null functions
-(define null '())
-(define (null? x) (= '() x))
-
-; booleans
-(define true (and))
-(define false (or))
-
-; list functions
-(define (length list)
-  (if (null? list)
-      0
-      (+ 1 (length (cdr list)))))
-
-(define (append list1 list2)
-  (if (null? list1)
-    list2
-    (cons (car list1) (append (cdr list1) list2))))
-
-(define (list-head list index)
-  (if (= index 0)
-    (car list)
-    (list-head
-      (cdr list)
-      (- index 1))))
-
-(define (list-tail list index)
-  (if (= index 0)
-    (cdr list)
-    (list-tail
-      (cdr list)
-      (- index 1))))
-
-(define (for-each list proc)
-  (while (not (null? list))
-    (proc (car list))
-    (set! list (cdr list))))
-
-(define (map list proc)
-  (if (null? list)
-    '()
-    (cons (proc (car list))
-          (map (cdr list) proc))))
-
-(define (inject list value proc)
-  (if (null? list)
-    value
-    (inject
-      (cdr list)
-      (proc value (car list))
-      proc)))
-""";
-}