+ ((prim (and lexed-ast (symbolp (car lexed-ast)) (find-prim (car lexed-ast)))))
+ (cond
+ ((and remaining-args (eql (car remaining-args) :done-with-args))
+ (append (when prev-item (list (help-arg prev-item prev-remaining-arg))) lexed-ast))
+ ((and prim (prim-is-infix prim))
+ (parse-prim prim lexed-ast prev-item prev-remaining-arg remaining-args)) ; Special casing infix prims is cleaner
+ (t
+ (append
+ (when prev-item (list (help-arg prev-item prev-remaining-arg)))
+ (cond
+ ((not lexed-ast) nil)
+ ((stringp (car lexed-ast))
+ (parse-internal (cdr lexed-ast)
+ :prev-item (car lexed-ast)
+ :prev-remaining-arg (car remaining-args)
+ :remaining-args (cdr remaining-args)))
+ ((numberp (car lexed-ast))
+ (parse-internal (cdr lexed-ast)
+ :prev-item (coerce (car lexed-ast) 'double-float)
+ :prev-remaining-arg (car remaining-args)
+ :remaining-args (cdr remaining-args)))
+ ((and remaining-args
+ (or
+ (eql :token (car remaining-args))
+ (and
+ (listp (car remaining-args))
+ (find :token (car remaining-args))
+ (symbolp (car lexed-ast)))))
+ (parse-internal (cdr lexed-ast)
+ :prev-item (car lexed-ast)
+ :prev-remaining-arg (car remaining-args)
+ :remaining-args (cdr remaining-args)))
+ ((eql (intern "(" :keyword) (car lexed-ast)) (parse-parened-expr (cdr lexed-ast) remaining-args))
+ ((eql (intern ")" :keyword) (car lexed-ast)) (error "Closing parens has no opening parens"))
+ ((eql :let (car lexed-ast)) (parse-let (cdr lexed-ast) remaining-args))
+ ((eql :[ (car lexed-ast)) (parse-block (cdr lexed-ast) remaining-args))
+ (prim
+ (when (prim-structure-prim prim)
+ (error "This doesn't make sense here"))
+ (parse-prim prim lexed-ast nil prev-remaining-arg remaining-args))
+ (t (error "Couldn't parse ~S" lexed-ast))))))))
+
+(defun parse-let (lexed-ast remaining-args)
+ (when (not (keywordp (car lexed-ast))) (error "Needed a keyword for let"))
+ (let*
+ ((half-parsed-remainder (parse-internal (cdr lexed-ast) :remaining-args (list t :done-with-args))))
+ (let
+ ((*dynamic-prims* (cons (list :name (car lexed-ast) :precedence 20) *dynamic-prims*)))
+ (parse-internal
+ (cdr half-parsed-remainder)
+ :remaining-args (cdr remaining-args)
+ :prev-remaining-arg (car remaining-args)
+ :prev-item (list :let (car lexed-ast) (cadr (car half-parsed-remainder)))))))
+
+(defun reconfigure-due-to-precedence (prev-item prim following-args)
+ (flet
+ ((calculate-precedence (x)
+ (or
+ (and
+ (listp x)
+ (< 1 (length prev-item))
+ (keywordp (car x))
+ (find-prim (car x))
+ (prim-precedence (find-prim (car x))))
+ 20)))
+ (cond
+ ((<= (prim-precedence prim) (calculate-precedence prev-item))
+ (cons
+ (prim-name prim)
+ (cons
+ (second (help-arg prev-item (car (prim-args prim))))
+ following-args)))
+ (t (append
+ (butlast prev-item)
+ (list
+ (reconfigure-due-to-precedence
+ (car (last prev-item))
+ prim
+ following-args)))))))
+
+(defun parse-prim (prim lexed-ast prev-item prev-remaining-arg remaining-args)
+ (when (not (prim-precedence prim))
+ (error "Prim must have a precedence! ~A" prim))
+ (when (and (prim-is-infix prim) (eql :token (car (prim-args prim))))
+ (error "Can't have a prim that wants a token in the first position while being infix: ~A" prim))
+ (when
+ (and
+ (< (prim-precedence prim) 20)
+ (find-if (lambda (arg) (or (eql :token arg) (and (listp arg) (find :token arg)))) (prim-args prim)))
+ (error "Can't have a prim that wants a token and has a precedence of less than 20: ~A" prim))
+ (let*
+ ((args (if (prim-is-infix prim) (cdr (prim-args prim)) (prim-args prim)))
+ (half-parsed-remainder
+ (parse-internal (cdr lexed-ast) :remaining-args (append args (list :done-with-args))))
+ (breakpoint (or
+ (position-if (lambda (form) (or (not (listp form)) (not (eql :arg (car form))))) half-parsed-remainder)
+ (length half-parsed-remainder)))
+ (already-parsed-limbo-forms
+ (subseq half-parsed-remainder breakpoint (min (length args) (length half-parsed-remainder))))
+ (num-optional-forms (- (length args) breakpoint))
+ (middle-forms
+ (cons
+ (if
+ (prim-is-infix prim)
+ ; There's a potential bug here about infix operators with optional forms, where the first item is optional
+ ; I don't consider that super likely though...
+ (append
+ (reconfigure-due-to-precedence prev-item prim (mapcar #'cadr (subseq half-parsed-remainder 0 breakpoint)))
+ (loop :repeat num-optional-forms :collect :optional))
+ (cons
+ (prim-name prim)
+ (append
+ (mapcar #'cadr (subseq half-parsed-remainder 0 breakpoint))
+ (loop :repeat num-optional-forms :collect :optional)))) ; we save the place for optionals for the transpiler
+ already-parsed-limbo-forms)));)
+ (let
+ ((arg-at-bp (nth breakpoint args)))
+ (when (and arg-at-bp (or (not (listp arg-at-bp)) (not (find :optional arg-at-bp))))
+ (error "Stopped collecting arguments, but non optional arguments remain")))
+ (append
+ (butlast middle-forms)
+ (parse-internal
+ (nthcdr (length args) half-parsed-remainder)
+ :remaining-args (if (prim-is-infix prim) remaining-args (cdr remaining-args))
+ :prev-remaining-arg (if (prim-is-infix prim) prev-remaining-arg (car remaining-args))
+ :prev-item (car (last middle-forms))))))
+
+(defun help-arg (arg arg-type)
+ (cond
+ ((not arg-type) arg)
+ ((eql arg-type :token) (list :arg (list :token arg)))
+ ((and (listp arg-type) (find :token arg-type) (symbolp arg)) (list :arg (list :token arg)))
+ ((eql arg-type :command-block)
+ (if (not (and (consp arg) (eql 'block (car arg))))
+ (error "Required a block, but found a ~A" arg)
+ (list :arg (cons :command-block (cdr arg)))))
+ ((eql arg-type :reporter-block)