(in-package #:fwoar.lisputils)
 
 (defmacro vector-destructuring-bind ((&rest symbols) vector &body body)
   (let ((mappings (loop for symbol in symbols

                         for num from 0
                         collect (list num symbol))))

     (once-only (vector)
       `(symbol-macrolet ,(mapcar (destructuring-lambda ((num symbol))

                                    `(,symbol (aref ,vector ,num)))

                           mappings)
          ,@body))))

 (defun v-assoc (item vector &key test test-not key)
   (loop for cur across vector
         for assoc-key = (car cur)
         for keyed = (if key (funcall key assoc-key) assoc-key)

         if (and test (funcall test item keyed)) do (return cur)

           else if (and test-not (not (funcall test item keyed))) do (return cur)
                  else when (eql item keyed) do (return cur)))

 
 (defun v-first (vector)
   (elt vector 0))
 
 (defun index-table (table &key (test 'eql) (key 'v-first))
   (declare (optimize (speed 0) (debug 3)))
   (check-type table (array * (* *)))
   (let ((table-index (cl-containers:make-container 'cl-containers:simple-associative-container :test test)))
     (loop for row-num from 0 to (1- (array-dimension table 0))

           for current-row = (make-array (array-dimension table 1)
                                         :displaced-to table
                                         :displaced-index-offset (apply #'array-row-major-index
                                                                        table (list row-num 0)))
           do (setf (cl-containers:item-at table-index (funcall key current-row)) row-num))

     table-index))
 
 (defun join-tables (table1 table2 &key (test 'eql) (key1 'v-first) (key2 'v-first))
   (declare (optimize (speed 0) (debug 3)))
   (check-type table1 (array * (* *)))
   (check-type table2 (array * (* *)))
   (let ((table2-index (index-table table2 :test test :key key2)))
     (loop for row-num from 0 to (1- (array-dimension table1 0))

           for current-row = (make-array (array-dimension table1 1)
                                         :displaced-to table1
                                         :displaced-index-offset (apply #'array-row-major-index
                                                                        table1 (list row-num 0)))
           for dest-index = (cl-containers:item-at table2-index (funcall key1 current-row))
           when dest-index
             collect (let* ((to-row (make-array (array-dimension table2 1)
                                                :displaced-to table2
                                                :displaced-index-offset (apply #'array-row-major-index
                                                                               table2 (list dest-index 0)))))
                       (concatenate 'vector current-row to-row)))))