1 files changed, 63 insertions, 0 deletions
diff --git a/extra.lisp b/extra.lisp
new file mode 100644
index 0000000..916465b
--- /dev/null
+++ b/extra.lisp
@@ -0,0 +1,63 @@
+(in-package #:monparser)
+
+(defmacro literal (word)
+  (when (not (stringp word))
+    (error "Literal only accepts strings as input."))
+  (let ((binding-list '())
+        (name-list '()))
+    (loop :for c :across word :do
+          (when c
+            (let ((name (gensym)))
+              (push name name-list)
+              (push `(,name (unit ,c)) binding-list))))
+    `(comp ,(reverse binding-list)
+           (coerce ,(cons 'list (reverse name-list)) 'string))))
+
+(defparameter nothing
+  (new nil))
+
+(defun optional (p)
+  (one-of p nothing))
+
+(defun many (p)
+  (comp ((x p)
+         (xs (if (not x)
+               (fail "Parsing result is empty.")
+               (optional (many p)))))
+        (cons x xs)))
+
+(defun repeat (p min &optional (max 0))
+  (if (> min 0)
+    (comp ((x p)
+           (xs (repeat p (1- min) (1- max))))
+          (cons x xs))
+    (if (> max 0)
+      (comp ((x (optional p))
+             (xs (repeat p 0 (if x (1- max) 0))))
+            (if x (cons x xs) x))
+      nothing)))
+
+(defun whitespace? (x)
+  (some (lambda (y) (char= x y)) '(#\Space #\Newline #\Tab)))
+
+(defparameter whitespace
+  (comp ((_ (optional (many (unit whitespace?)))))
+        :whitespace))
+
+(defun separated-list (p separator &key include-separator)
+  (comp ((v p)
+         (sep (optional separator))
+         (vn (if sep
+               (separated-list p separator)
+               nothing)))
+        (if include-separator
+          (cons v (cons sep vn))
+          (cons v vn))))
+
+(defun surrounded (left p right &key include-surrounding)
+  (comp ((l left)
+         (body p :lazy)
+         (r right))
+        (if include-surrounding
+          (list l body r)
+          body)))